Did you put holes/slashes in the top before baking? If not, the hot air has nowhere to escape and there's your air pocket.

That is not uncommmon. Even with slashes. Your fruit cooks down and leaves that empty spot quite often. Especially with fruit like apples, which are bulky. Nothing wrong with it.

That happens....the crust cooks and the filling cooks down and leaves a gap....
if you cook the pie a little less time it wont' be so pronounced...but it's there....just push down the top crust with your hand!
And remember soem fruits cook down more than others....some apples cook way down and some don't.
How'd it taste?? That's what counts!
Linda C

Cooks Illustrated suggests a method of cooking down apples a bit before putting them in a pie. I tried it and ended up with something like a 4" tall pie with no gap. I would guess that this method could translate to other fruit as well.

Yes, I put slashes in the top pie crust, and the pie tastes divine anyways. I just don't like that gap!

Foodonastump, how do I - and how long - should I cook down my apples, when I make my apple pie?

thanks, TammyPie

Sometimes the juices can actually seal up your slashes. I've found that inserting a knife in the slashes about halfway through the baking time helps.

Nancy

I thought I remembered them being really particular about the cooking temp on the show, but that does not seem to be reflected here.

Deep-Dish Apple Pie
Cooks Illustrated, 9/2005

Use a combination of tart and sweet apples for this pie. Good choices for tart are Granny Smiths, Empires, or Cortlands; for sweet, we recommend Golden Delicious, Jonagolds, or Braeburns. Wrap leftovers tightly in plastic wrap and store at room temperature for up to 24 hours. To reheat, remove the wrap and warm the pie in a 350-degree oven for 15 to 20 minutes. See below for freezing instructions.

Makes one 9-inch pie, serving 8 to 10

All-Butter Pie Pastry
2 1/2 cups unbleached all-purpose flour (12 1/2 ounces), plus additional flour for work surface
1 teaspoon table salt
1 tablespoon sugar
16 tablespoons unsalted butter (2 sticks), cold, cut into 1/2-inch cubes and frozen for 10 minutes
3 tablespoons sour cream
1/3 cup ice water , or more if needed
Apple Filling
1/2 cup granulated sugar (3 1/2 ounces), plus 1 teaspoon
1/4 cup packed light brown sugar (1 3/4 ounces)
1/4 teaspoon table salt
1 tablespoon lemon juice
1/2 teaspoon grated lemon zest
1/8 teaspoon ground cinnamon
2 1/2 pounds tart apples (firm), about 5 medium, peeled and cut into 1/4-inch-thick slices (see note)
2 1/2 pounds sweet apples (firm), about 5 medium, peeled and cut into 1/4-inch-thick slices (see note)

1 egg white , beaten lightly

1. For Pastry: Process flour, salt, and sugar together in food processor until combined, about 3 seconds. Add butter and pulse until butter is size of large peas, about ten 1-second pulses.

2. Using fork, mix sour cream and 1/3 cup ice water in small bowl until combined. Add half of sour cream mixture to flour mixture; pulse for three 1-second pulses. Repeat with remaining sour cream mixture. Pinch dough with fingers; if dough is floury, dry, and does not hold together, add 1 to 2 tablespoons ice water and process until dough forms large clumps and no dry flour remains, three to five 1-second pulses.

3. Turn dough out onto work surface. Divide dough into 2 balls and flatten each into 4-inch disk; wrap each disk in plastic and refrigerate until firm but not hard, 1 to 2 hours, before rolling. (Dough can be refrigerated for up to 24 hours. Let thoroughly chilled dough stand at room temperature for 15 minutes before rolling.)

4. For Pie: Mix 1/2 cup granulated sugar, brown sugar, salt, zest, and cinnamon in large bowl; add apples and toss to combine. Transfer apples to Dutch oven (do not wash bowl) and cook, covered, over medium heat, stirring frequently, until apples are tender when poked with fork but still hold their shape, 15 to 20 minutes. (Apples and juices should gently simmer during cooking.) Transfer apples and juices to rimmed baking sheet and cool to room temperature, about 30 minutes. While apples cool, adjust oven rack to lowest position, place empty rimmed baking sheet on rack, and heat oven to 425 degrees.

5. Remove 1 disk of dough from refrigerator and roll out between 2 large sheets of parchment paper or plastic wrap to 12-inch circle, about 1/8 inch thick. (If dough becomes soft and/or sticky, return to refrigerator until firm.) Remove parchment from one side of dough and flip onto 9-inch pie plate; peel off second layer of parchment. Working around circumference, ease dough into plate by gently lifting edge of dough with one hand while pressing into plate bottom with other hand. Leave dough that overhangs plate in place; refrigerate until dough is firm, about 30 minutes.

6. Meanwhile, roll second disk of dough between 2 large sheets of parchment paper or plastic wrap to 12-inch circle, about 1/8 inch thick. Refrigerate, leaving dough between parchment sheets, until firm, about 30 minutes.

7. Set large colander over now-empty bowl; transfer cooled apples to colander. Shake colander to drain off as much juice as possible (cooked apples should measure about 8 cups); discard juice. Transfer apples to dough-lined pie plate; sprinkle with lemon juice.

8. Remove parchment from one side of remaining dough and flip dough onto apples; peel off second piece of parchment. Pinch edges of top and bottom dough rounds firmly together. Following illustrations 1 through 4, trim and seal edges of dough, then cut four 2-inch slits in top of dough. Brush surface with beaten egg white and sprinkle evenly with remaining teaspoon sugar.

9. Set pie on preheated baking sheet; bake until crust is dark golden brown, 45 to 55 minutes. Transfer pie to wire rack and cool at least 1 1/2 hours. Cut into wedges and serve.

Isn't that extra room for filling with ice cream? ;-)

To prevent this I sometimes crimp the bottom crust and use a dinner plate to cut the top crust so that it is just slightly smaller than the pie (so it floats on top of the filling.) I use tiny aspic cookie cutters to decorate it before setting it on top of the filling. While it bakes the 'free standing' top crust stays on the filling nicely. The cherry/raspberry pies in the picture have this kind of floating top crust. The other pies are peach custard, and have no top crust. I should have taken a picture before the pies were sliced so you could have had a better image.