blueberry slab pie

We’re back after taking a week off with our 35th bake from Claire Saffitz’s Dessert Person. This latest recipe from the Pies and Tarts chapter is the epic Blueberry Slab Pie.

Lauren’s Take

Hello and happy weekend everyone! Despite the intense heat and humidity in the air right now, there is also that quintessential August feeling of the summer being almost over. And with that, the end of fresh fruit and warm days, so it was nice to be able to bake a very summer-y dessert to commemorate that! And what says end of summer like a nice slice of blueberry pie?

This pie is a beast. When you first glance at the recipe, it doesn’t seem to be that big of a task but then there are a few hints that really allude to the monstrosity… namely that it “feeds 24” and the casual “1.6kg of blueberries” listed in the ingredients. I mean, 1.6kg?! Just wild. I was really praying that this bake would turn out because I would have to give a lot away and wanted it to be worth people’s while. Initially, I was a bit nervous because Claire classifies this bake with a difficulty level of 4, but in all honesty, it truly isn’t that difficult. The hardest part is ensuring you have a large enough work space to roll out these monster pieces of dough, but otherwise, it was fairly simple to put together (as long as you can find 1.6kg of blueberries—clearly I’m still not over that).

The first part of the bake is to make two batches of the pie dough. The dough for this recipe is essentially the same as her other pie dough recipe, just a lot more of it and A LOT of butter. You think 1.6kg of blueberries is a lot, well try 6 sticks of butter…which is what this recipe calls for. You combine the flour, sugar, salt, and butter together in a food processor and then slowly add water and mix with a fork/by hand until the dough holds together. This step is repeated twice (because even a large food processor can’t handle this much dough at once!), and then you are left with two large pieces of dough, which are wrapped and chilled in the fridge for at least two hours.

Once the pie dough has chilled, the real fun of rolling begins. No word of a lie, I had my ruler out and was meticulously measuring to make sure I got these pieces of dough to the appropriate size! One piece of dough you roll out to about 18 by 15 inches and cut it into 1.5inch wide strips that are about 15 inches long. I got about 12-13 strips from my dough. Once the strips are cut, you place them back in the fridge to keep chilled. Then you roll out the other piece of dough, which will be for the bottom of the slab pie. This piece is rolled even larger, I believe I did it to about 21 by 16 inches or so. You then carefully place it in your sheet pan, which should be 18 by 13 inches, leaving an inch or so of the dough overhanging.

The oven needs to be pre-heated to 425 degrees, and Claire recommends baking this pie on the lowest rack in the oven. I lined my oven rack with aluminum foil as suggested in the book to prevent any burning from spillage while baking. A tip that Claire gives is to put ANOTHER 18 by 13 pan in the oven while it is pre-heating, and then places your sheet pan with the pie INSIDE the sheet pan in the oven. Now, I do believe this is a great tip, but lord knows it was hard enough for me to find one massive sheet pan, never mind two! So I just baked my pie directly on the oven rack and it worked out fine! No soggy bottoms here friends.

After the pie dough is rolled out, you mix your filling, which was very simple. In a LARGE bowl (and it needs to be large because, remember, you got pounds on pounds of blueberries), you mix your berries with sugar, cornstarch, lemon zest, lemon juice, vanilla, and the spices. In this recipe, Claire uses cinnamon, cardamom, and ginger. I was intrigued by this blend, since it is very much gives me a pumpkin-pie vibe, but I followed the recipe.

You pour the filling into the sheet pan and even it out all over. Then you brush the overhang of the pie dough with egg wash, and press your chilled strips of pie dough across the filling and into the border. Claire describes placing them on a diagonal in a zig-zag pattern, but you could really do whatever you want, as long as it’s covered. I made sure to place the strips fairly close together but still had spots where you could see the filling pop through. I did end up having two strips left over as well. Once the strips are placed and pressed, you cut off the extra dough and fold the overhang back overtop and press down again. Then the whole pie is brushed with egg wash and covered with Demerara sugar (I was generous here, but not as generous as Julia usually is with Demerara sugar 😉). Then, you bake! One of the hardest parts of this bake was lifting this beast into the oven, so take your time and be careful!

The pie bakes on 425 degrees Celsius for 20 minutes, and then the oven is reduced to 375 degrees for the remainder. I baked the pie for another hour and 35 minutes after turning the oven down to ensure a nice golden crust and bubbly filling. I didn’t end up having any spillage in the oven from the filling which was nice. The crust baked beautifully and the design with the sugar on top made it beautiful to look at.

After letting it chill for an hour, it was time to cut into it and try it! I don’t love warm fruit pie, so initially I wasn’t a huge fan. The filling felt too soft and the spices made it taste like pumpkin pie which confused me. I did really love the pie dough, but overall wasn’t a huge fan. Then, the next day, I was getting praise about this pie from people I had given it to, so I decided to take another stab at it, and I liked it quite a bit more. The filling is more set, the spices don’t seem as overpowering, and overall, it feels well balanced and flavoured. I’m still not 100% sure I agree with the spice combo here…I think maybe just cinnamon and cardamon would have been a better choice, without adding the ginger. I also think you could add more lemon funnily enough, since I find Claire is usually too heavy-handed with the citrus, but I think when you’re making a pie large enough to feed a small village, you can be a bit freer with flavour.

So overall, not my favourite pie, but it does get better with age for sure. Definitely a really nice recipe to have if you need to bake something for a large gathering. And the pie dough is never a disappointment as per usual. 3.5 stars for me!

Julia’s Take

Welcome back everyone! It’s been a whirlwind couple of weeks over here as I wrap up my summer holidays. Lots of social time and out-of-town visits means I’ve been spending very little time at home (a welcome change after pandemic lockdown life!) and very little time in my kitchen, so our Blueberry Slab Pie was put on the back-burner. But it feels good to be back in action—although I am definitely not ready to go back to work already.

This recipe was HEFTY and the amount of ingredients it called for was no joke. So many cups of flour. So many pounds of blueberries. The six sticks of butter especially left me shaken. SIX STICKS! I was surprised Claire listed this pie as a difficulty level four because other than the measuring out of ingredients (and the heavy lifting) it was actually a really simple recipe to put together. I had set aside an evening to bake this pie last week since I knew I would be out of town for the majority of the upcoming two weeks, and while I thought I’d budgeted out my time well, things didn’t exactly go according to plan. I started out by making my dough in the morning. The ingredients are exactly the same as the Flaky All-Butter Pie Dough that we all now know and love so well; the only difference was that—since there was so much of it for this recipe—it came together in two batches in the food processer (one batch for the bottom of the pie and one batch for the strips on top), and we skipped the folding step. Once I had my dough mixed up, I let them sit in the fridge for the rest of the day while I met a friend for lunch and did a bunch of running around.

By the time I got home around 4:00, my pie dough was ready and I could get started on the filling and assembly. I had promised my neighbour I’d go over for a quick glass of wine to wish her Happy Birthday. Little did I know I would not actually return home until 11:30. So when a girl gets home late and has had a few glasses of wine but a pie needs baking, she bakes the pie.

 

 

Luckily, there wasn’t too much work involved in finishing things up. My bottom layer of pie dough was rolled out and placed into the 18×13” pan; the filling came together with tons of blueberries (I used fresh ones which are in season in Ontario right now!), sugar, cornstarch, lemon juice and zest, vanilla, and a spice combo of cinnamon, cardamom, and ground ginger. From my understanding, cardamom and ginger are NOT common in blueberry pie, but we all know our girl Claire LOVES her cardamom. Honestly, I’m sure some people are hit and miss on these flavours, but personally I thought it was such a unique and delicious spin and I really loved the smell of everything as it all came together.

The filling then gets poured into the bottom layer of dough. My top layer had been cut into 1” strips (not my neatest or most mathematically correct work, to be honest—see time stamp on when I started this pie and just imagine how alert I probably was…) but once I placed everything on top of the blueberries it looked fine. The slab pie ultimately has a bit of a rustic feel to it anyway, so this worked out in my favour. Note to self: don’t start croquembouche at 11:30pm after a few glasses of wine.

The whole thing probably came together in half an hour, so then the hardest part was really just trying to stay awake while the pie baked for almost two hours. Claire provides a couple of suggestions to help with the baking: first, cover the bottom oven rack with tin foil in case there’s spillage (I did do this, and my oven came out unscathed), and also put a second pan in the oven to preheat, which the pie can then sit in while it bakes to help with the crispiness of the bottom. I didn’t have a second 18×13” pan so I skipped this step and my results were still fantastic! I almost fell asleep several times, but by 1:30am I had a beautiful, bubbly, crispy blueberry pie sprinkled with demerara sugar (my new favourite thing. See: Sour Cherry Pie). My favourite part of this bake was definitely the smell of the spices that filled up the house; it was sort of like summer and fall coming together—kind of appropriate for end of August and almost-back-to-school/work vibes.

I gave away the majority of this pie: big pieces were dropped off to friends the next morning on my way out of town, and I also brought a WHOLE bunch of it to the friends I was staying with down in Southern Ontario. Everyone really loved the flavour. It wasn’t my favourite thing from this chapter; if I’d just had this pie on its own, I may have felt differently, but compared to some of the epic pies and tarts we’ve had over the last few weeks, this one felt just sort of “meh” to me. Similar to many of the loaves and single layer cakes we made, this pie did get a lot better as the temperature came down and it set a little more. Absolutely delicious, but not necessarily life-changing. It’s a 3.5 star bake from me!

Join us next week as we make the second-last recipe from the Pies and Tarts chapter—the much-anticipated Peach Melba Tart!