Preheat Oven: Place a large baking sheet on the middle rack of the oven and preheat the oven (with the pan inside) to 375 degrees F. (This is optional, but cooking the pie on a hot baking sheet will help the bottom crust cook and not be soggy.)

Place rolled out pie crust dough into pie pan. Refrigerate while you make filling.

Make the Crumb Topping: Combine flour, oats, brown sugar, cinnamon, and nutmeg, in a bowl. Add butter and use your fingertips, a fork, or pastry blender to work the butter into the mixture until well combined. Refrigerate while you assemble the pie.

Make Filling: Add pears to a large mixing bowl. Sprinkle lemon juice, butter, sugars, flour and spices over the top and very gently stir to coat evenly. Pour filling into pie shell. Top with crumb topping.

Bake: Place pie in the oven on top of a hot baking sheet and bake for about 50 minutes, until filling is bubbling and the crust is golden.

Cool: Remove the pie from the oven and allow to cool completely on a wire rack, at least 3 hours, before cutting and serving. This allows the filling to set up so it won’t fall apart when slicing.

Serve with a scoop of vanilla ice cream and a drizzle of caramel sauce, if desired.