Blind baking means to partially or completely bake a pie or tart shell/crust before filling it. This technique is particularly useful when making pies that have very juicy fillings like a fruit pie, as they will cause the bottom of the pie to become soggy. Blind baking the crust prevents the crust from absorbing too much liquid. Other pie and tart fillings, such as a custard, require no baking so the crust will need to be fully baked prior to adding any filling.
To blind bake a crust, carefully roll out the pie dough then place it into a pie pan. Once the dough is fitted into the pan lay a sheet of tin foil or parchment paper on top and weigh it down with pie weights, dried beans, or raw rice. Bake according to the recipe instructions. If partially blind baking the crust, remove from the oven when the sides are just set but the crust is still pale. If completely blind baking the crust, remove from the oven when the crust is a deep golden brown. If the filling is not being baked in the crust, cool completely to prevent any sogginess.