Blind baking, also known as pre-baking, refers to baking an empty pie or tart crust. Blind baking is necessary when the filling cannot be baked as long as the crust, or if the filling would make the crust too soggy when added. Oftentimes pastry weights are placed inside to help the pastry keep its shape when baking. If you don’t have pastry weights, line the crust with parchment paper or a coffee filter and fill with beans or rice, taking care to push them up against the sides of the crust. Avoid using foil, which doesn’t allow the pastry to breathe.