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This flat apple pie has all the cozy flavor of an old-fashioned fried apple pie without the frying. The flaky crust, cinnamon-sweet apples, and thin vanilla frosting make every square irresistible. You’re going to love how easy it is to slice, serve, and eat.
Why You’ll Love It
- Easy cookie-sheet pie — no deep dish, crimped edge, or fussy pie shaping required.
- No soggy crust — Corn Flakes catch the apple juices between the crust and filling.
- Feeds a crowd — makes about 15 squares, depending on how generously they are cut.
- Faster cooling — the flat shape cools more quickly than a big round pie.
- Great any way — delicious warm, at room temperature, or cold from the refrigerator.
Ingredient Notes
Use Granny Smith apples if you can. Their tartness holds up beautifully against the sugar and frosting, and they stay pleasantly apple-ish instead of turning into anonymous sweet mush. The original amount is 10 apples, though apples vary wildly in size now. Some are practically softball-sized. Eight large apples can be plenty; ten medium ones is about right.
For the shortening, use the plain old vegetable shortening. This is one of those recipes where I don’t get cute with butter in the crust, even though I adore butter and have been known to put it on things that absolutely did not need it. The shortening gives this crust that tender, flaky texture that makes the whole pie feel a little like those handheld fried pies from the drive-thru place with the golden arches. You know the one. No need to name names.
The egg is divided here: the yolk goes into the crust mixture with enough milk to make one cup of liquid, and the egg white gets beaten with sugar for brushing over the top. It sounds a little fussy written out, but it isn’t. Just separate the egg before you get going.
Ingredients
- 3 3/4 cups all-purpose flour
- 3/4 teaspoon salt
- 1 1/2 cups shortening
- 1 egg yolk, plus enough milk to make 1 cup of liquid
- 2 to 3 handfuls Corn Flakes, lightly crushed if you feel like it—I usually just crush them a bit in my hand
- 10 Granny Smith apples, cored and sliced (8 large apples can work just fine)
- 4 to 8 tablespoons butter, cubed; I lean toward 6, but that’s just me
- 1 cup sugar
- 1 teaspoon cinnamon
- 1 egg white
- 1 teaspoon sugar
Thin Frosting
- 2/3 cup powdered sugar
- 2 to 3 dashes vanilla extract
- Milk, enough to make a thin, drizzle-able frosting
Instructions
Heat your oven to 425°F. Use a 15-by-10-inch cookie Sheet Pan—the kind with a little rim around it, not a completely flat baking sheet unless you enjoy living dangerously with apple juices. I do not.
Make the crust by mixing the flour, salt, shortening, and the egg-yolk-and-milk mixture. For that liquid, put the egg yolk in a measuring cup, then add enough milk to reach 1 cup total. Work the dough together until it comes together nicely. Don’t beat it to death. Pie dough can sense fear and resentment, I’m convinced.
Divide the dough in half. Roll out one half large enough to fit your cookie sheet, then carefully settle it into the pan. Patch any tears with a little extra dough. Nobody sees the bottom anyway, and anybody who critiques your pie crust can bring dessert next time.
Scatter 2 to 3 handfuls of Corn Flakes over the bottom crust. You want a light covering, not a breakfast buffet.
Arrange the sliced Granny Smith apples over the Corn Flakes. They can overlap and mound up a little. They will cook down, so don’t panic and start removing apples. Neat is overrated.
Mix the 1 cup sugar and cinnamon together, then sprinkle it evenly over the apples. Dot the top with the cubed butter. The range of 4 to 8 tablespoons sounds like a lot, but it depends on your apples and your general philosophy about butter.
Roll out the remaining dough and place it over the apples. Trim or tuck the edges as needed, then cut a few slits in the top so steam can escape. Do not skip the slits.
Beat the egg white with 1 teaspoon sugar and brush it over the top crust. This gives the pie a pretty, lightly crisp finish. Bake for 25 to 30 minutes, until the crust is golden and you can see little signs of bubbling around the edges.
While the pie is still hot, stir together the powdered sugar, vanilla, and enough milk to make a thin frosting. Thin means it should drizzle easily from a spoon—not sit there in a gloppy lump like school paste. Drizzle it all over the hot pie. Some will melt in, some will stay white on top, and it will look exactly right.
Variations
Add a little extra cinnamon, and sometimes a pinch of nutmeg. A tiny pinch is nice, especially around the holidays when every candle in the store smells like a lumberjack’s sweater and you’re trying not to buy another one.
You could use a mix of tart apples and sweeter apples, though I still prefer Granny Smiths here. I tried this once with all Honeycrisp apples because they were on sale, and the pie tasted good, but the filling was sweeter and softer than I wanted. Not bad—just not this pie. This pie needs a little tang to keep it from becoming a sugar situation.
I’ve also seen people leave off the frosting, and yes, technically you can. But why? The frosting is not heavy; it’s just that little sweet vanilla veil over the crust. Leave it off if you must. I’ll try not to take it personally.
Storage & Reheating
Cover leftover pie loosely and keep it at room temperature for a day, or refrigerate it for up to 3 days. Ours rarely lasts that long.
For reheating, pop a square into a 300°F oven for 8 to 10 minutes if you want the crust to perk back up. The microwave works in a pinch—20 seconds or so—but the crust gets softer. Still delicious, just softer. Sometimes that is exactly what you want when it’s late and the kitchen is quiet and you’re not interested in preheating one single thing.
Cold squares are good, too. Better than they have any business being, honestly.
Final Notes
There’s something about a cookie-sheet dessert that makes a kitchen feel full, even when it isn’t. Maybe it’s because it’s wide and golden and smells like cinnamon before the first bite.
The pie still comes out of the oven with that same buttery smell. Either way, there’s a square waiting on the counter.
Flat Apple Pie
Ingredients Â
- 3 3/4 cups all-purpose flour
- 3/4 teaspoon salt
- 1 1/2 cups shortening
- 1 egg yolk plus enough milk to make 1 cup of liquid
- 2 to 3 handfuls Corn Flakes lightly crushed, if desired
- 10 Granny Smith apples cored and sliced; 8 large apples can work just fine
- 4 to 8 tablespoons butter cubed
- 1 cup sugar
- 1 teaspoon cinnamon
- 1 egg white
- 1 teaspoon sugar
- 2/3 cup powdered sugar
- 2 to 3 dashes vanilla extract
- milk enough to make a thin, drizzle-able frosting
InstructionsÂ
- Heat the oven to 425°F and use a 15-by-10-inch rimmed cookie sheet pan.
- Make the crust by mixing the flour, salt, shortening, and the egg-yolk-and-milk mixture; to make the liquid, place the egg yolk in a measuring cup and add enough milk to reach 1 cup total, then work the dough together just until it comes together nicely.
- Divide the dough in half, roll out one half large enough to fit the cookie sheet, and carefully settle it into the pan, patching any tears with a little extra dough.
- Scatter 2 to 3 handfuls of Corn Flakes over the bottom crust in a light covering.
- Arrange the sliced Granny Smith apples over the Corn Flakes, allowing them to overlap and mound slightly because they will cook down.
- Mix the 1 cup sugar and cinnamon together, sprinkle it evenly over the apples, and dot the top with the cubed butter.
- Roll out the remaining dough and place it over the apples, then trim or tuck the edges as needed and cut a few slits in the top so steam can escape.
- Beat the egg white with 1 teaspoon sugar, brush it over the top crust, and bake for 25 to 30 minutes, until the crust is golden and there are little signs of bubbling around the edges.
- While the pie is still hot, stir together the powdered sugar, vanilla, and enough milk to make a thin frosting that drizzles easily from a spoon, then drizzle it all over the hot pie.