Prepare the pie crust if you are making homemade pie crust. Refrigerate for several hours or overnight. In a large bowl, use a large spoon or rubber spatula to stir together the peaches with lemon juice, sugar, tapioca, cinnamon and nutmeg until combined. Set aside.
On a lightly floured work surface, roll out the bottom crust slightly larger in diameter than your baking dish. Gently place the pie crust into the pan lightly, using your fingers. Use kitchen shears to trim the edges of the crust, to about ¾-inch past the pan rim.
Place the pie shell into the freezer for 30 minutes or an hour to firm up. This will help it hold it's shape.
Use a slotted spoon to scoop the peach filling into the pie crust. Discard the remaining lemon juice.
Trim the edges of pie crust with kitchen shears and roll under the crust. Crimp with your fingers or press with a fork.
Sprinkle the crumb topping over the peaches.
Brush the pie crust edges with an egg wash.
Place the pie on a half sheet pan lined with parchment paper. This will help catch any juices that run over the edges of the pie plate.
Place in a preheated 400 degree F oven for 1 hour. The crust will be golden brown and the filling bubbling up around edges of the crust.
Part way through baking, cover the pie with a piece of aluminum foil you have cut a hole in the center. This will help the pie continue cooking, but let steam escape so your pie crust does not become soggy. This will prevent the edges of the pie crust from becoming too brown.
Let cool for at least an hour or two before slicing. This will allow the pie filling to set.