This slab pie is truly a masterpiece and I’m not afraid to say it. I made it for Kramer’s birthday barbecue last month. We were laying in bed one night, having our usual 10 minute conversation before rolling over and trying to go to sleep, when I asked what dessert he wanted for his birthday. We started thinking out loud (I think out loud to Kramer with most recipes – he is my Nielsen box). Something chocolate? Something peanut butter? He suggested something with s’mores. S’mores cake? S’mores cookies? How about a giant s’mores pie? A giant s’mores Pop-Tart! That was it. I had to make it. A s’mores Pop-Tart would be enough to feed a crowd while still being interesting and impressive. I had made a slab pie last year and people really enjoyed it. I love slab pies (like this Triple Berry Slab Pie) because you have the option of just cutting yourself a square and eating it with your hands. What better way to make a giant Pop-Tart, since they are meant to eaten with your hands, anyway?
I used my usual pie crust for this, as it’s never failed me before. I think that I even did an all butter crust this time around, although I really don’t recommend it. I know that a lot of people say that all butter crusts are the best, but maybe they’ve never worked with a half shortening, half butter crust. It rolls out like a dream and the shortening helps the crust hold up much better in summer baking conditions, as it has a higher melting point. Between that, and being sure to chill the dough for a minimum of 3 hours (this is key for any good pie crust), it’s what I consider to be the best. This crust has seen me through many a recipe and I’ll never abandon it. After the crust, though, I had to made my own chocolate filling (easy – thanks to A Cozy Kitchen) and my own marshmallow (scary). If you follow the blog, you’ll know that my Homemade Marshmallow Fluff fears were unwarranted – the recipe from Chow was flawless. After that, it was just a matter of slapping everything together and baking for about an hour. This giant Pop-Tart turned out beautifully. A buttery crust, a rich chocolate interior and plenty of creamy marshmallow goodness is the perfect way to make a crowd of people smile with nostalgia. I know it seems like a bit of work, but you can make everything separately and then build the pie on another day. It’s worth it!
It’s funny that I’m posting the pie today, because we had another barbecue over the weekend (sadly, sans pie, but with lots of giant chocolate chip cookies). We did another clam bake, which went swimmingly last year so we decided to go for broke and try it again. I think that this year’s was even better than last year’s. We had mountains of clams, shrimp, sausage, corn and potatoes, alongside plenty of homemade bread. That was Saturday. On Friday, Kramer and I each had drinks with separate friends, then met up back home, ordered Vietnamese food and got to bed early, in preparation for the next day’s events. On Sunday, we slept in a bit, then I made some roasted pork and more cookies for another friend’s barbecue, although this time Kramer and I were not in charge of food, so we were able to sit back, relax and watch another couple man the grill. There was brisket and grilled wings, so I was happy. We walked home after the barbecue, then stopped by a bar for a few drinks and to watch the US play in the World Cup. Kramer and I treated ourselves to some ice cream that night (we deserve it!) and got to bed early enough to wake up rested and ready to go on Monday morning. It was a fun, food-filled weekend, indeed.
The key to this pie is working efficiently – make your chocolate, prep your pie crust, then put it all together.
Then, in no time, a giant s’mores Pop-Tart awaits!
Spread your glaze over top and enjoy.
- 7½ cups all-purpose flour
- ¼ cup + 2 tablespoons granulated sugar
- 1 teaspoon kosher salt
- 1⅓ cups unsalted butter, COLD (NOT room temperature), cut into pieces
- 1⅓ cups shortening, COLD (NOT room temperature)
- 1⅓ cups ice water
- 4 teaspoons distilled white vinegar
- ¾ cup granulated sugar
- ½ cup light corn syrup
- ¼ cup water
- ⅛ teaspoon kosher salt
- 2 large egg whites, at room temperature
- ¼ teaspoon cream of tartar
- 1½ teaspoons vanilla extract
- ¼ cup unsweetened cocoa powder
- ⅓ cup heavy cream
- ⅔ cup dark chocolate, chopped (or dark chocolate chips)
- 2 tablespoons granulated sugar
- 1 tablespoon butter, cubed
- pinch kosher salt
- ½ cup powdered sugar
- 3 tablespoons cocoa powder
- ¼ cup heavy cream
- Pie Crust
- Marshmallow Fluff
- Chocolate Filling
- 4 Graham Crackers, crushed (optional)
- 1 egg, lightly beaten + 1 teaspoon water
- Chocolate Glaze
- Whisk together the flour, sugar, and salt in a large bowl or the bowl of your food processor. I used my food processor, but I didn’t always have one and have had great results making this crust by hand. Please note that this is basically a double pie, meaning it is a lot of dough! I did mine in two batches (i.e. divided the recipe in half, which is my go-to regular pie crust, and did it two times - if you have a giant mixing bowl or food processor, go for it, but my equipment isn't large enough to handle 7½ cups of flour).
- Add in the chopped pieces of cold butter and cold shortening . Blend together with your hands or pulse with your processor until you have coarse crumbs (it doesn’t have to be perfect). You can use a pastry cutter, too, but I find that a clean pair of hands work best. Mix together the water and vinegar in a small bowl. When ready, slowly drizzle it over the dough, a tablespoon or so at a time, gently stirring the mixture with a fork or pulsing with your processor, until fully incorporated (you may not use all of the water).
- It might seem a bit too wet at this point, but it will dry up while it sits in the fridge. Form the dough gently into 2 loose balls, wrap tightly in plastic wrap, and chill in the fridge for a minimum of 3 hours or as long as overnight (as always, overnight is best). Make your filling when you are almost ready to use your dough.
- Stir together the sugar, corn syrup, water, and salt in a small saucepan over high heat. Bring the mixture to a boil, stirring often, until the it reaches 240 degrees F on a candy/fat thermometer. Be careful not to let the mixture bubble over - turn the heat down if you need and keep a watchful eye over it. This might take a little longer than you think, but just keep at it. Mine took about 10 minutes, but when you're standing there watching it, it feels like an eternity. It got stuck at around 220 for what seemed like forever, but then it eventually got up to 240.
- Place the egg whites and cream of tartar in the bowl of a stand mixer fitted with a whisk attachment. Start whipping the egg whites to soft peaks on medium speed. You want to have the egg whites whipped and ready to go, waiting for your syrup to be drizzled in. If they’re whipping faster than your syrup is coming to temperature, just stop the mixer until the syrup is ready, which is what I did.
- When the syrup reaches 240 degrees F, reduce the mixer speed to low and slowly drizzle about 2 tablespoons of syrup into the egg whites to warm them. If you add too much syrup at once, the whites will scramble. Slowly drizzle in the rest of the syrup, a bit at a time - seriously, do not do more than 2 tablespoons at a time.
- Increase the speed to medium high and whip until the marshmallow fluff is stiff and glossy, about 7 solid minutes. Don't try to speed this process up! Add in the vanilla and whip 2 minutes more. Use the fluff immediately or refrigerate stored in an airtight container for up to 2 weeks. I made my fluff about 4 hours ahead of time before baking with it, and I actually doubled the recipe so that I'd have some extra to spread of the top of the pie pieces...just an idea!
- If you have a double boiler, great, use that, but I don't, so I just melt chocolate very slowly and carefully because it burns easily. In a saucepan, combine your cocoa powder, heavy cream, chocolate, sugar, butter and salt. Stir over medium-low heat constantly until everything is melted and smooth. Remove from the heat and set aside. The mixture will thicken up as it cools down, making it easy to spread over your pie crust later.
- Remove your crust from the refrigerator to allow for easier rolling. Preheat your oven to 400 degrees F. Generously butter a 9x13-inch baking sheet.
- Roll out your first ball of dough - it should be about 10x14 or 11x15, if you can get it to stretch that far - it does not have to be perfect by any means. If you need to re-roll a few scraps here and there to patch up pieces, that's fine - I did it! It will all bake together in the end. Roll out your rectangle, then fold it over onto itself to more easily move it over onto the baking sheet. Unfold it and gently press the pie crust into the bottom of the 9x13-inch baking sheet.
- Spread your chocolate mixture over the dough, then spread the marshmallow mixture over the top of that. You may have a bit extra - this is your baker's reward! Sprinkle 4 crushed graham crackers over the top of the marshmallow. Roll out your second pie crust and gently place it over the top. Crimp the edges together, discarding any scraps (or using them to decorate the pie, dealer's choice).
- Use a fork to make a pattern in the top of the pie (see photos), like a traditional s'mores Pop-Tart. Beat together your egg and water and brush the top of the pie with it. Place the pie in the oven, the reduce the heat to 375 degrees F. Bake for 50-60 minutes, until golden brown and shiny on top. Remove from the oven and allow to cool slightly.
- If you like, you can add a chocolate glaze on top. Whisk together your powdered sugar, cocoa powder and heavy cream. It should be a thin consistency. Spread the glaze over the top of the pie. Allow the pie to cool completely (you can put it in the fridge, if you want - I recommend this if it's a hot summer day), then slice, serve and enjoy!