Why does my pumpkin pie crack on top?
When pumpkin pie is baked too long, it is likely to get cracks along the top surface and perhaps pull away from the crust along the edges. Also, if you bake the pie too high in the oven (rather than on the middle rack, the surface may be subject to too much direct heat, which causes a “skin” to form. As the pie cools, the dry, taut skin doesn’t settle with the filling, and ends up cracking and pulling away from the edges.
Recipe: Pumpkin-Maple Pie