Blind-baking

Blind baking a pie crust is necessary when it will be filled with an unbaked filling (such as with pudding or cream pies), in which case the crust must be fully baked.

[1] Blind baking is also used to keep pie crust from becoming soggy due to a wet filling.

In one technique, the pie crust is lined with aluminium foil or parchment paper, then filled with pastry- or pie weights (sometimes called "baking beans") to ensure the crust retains its shape while baking.

Pie-weights are available as ceramic or metal beads, but rice, dried peas, lentils, beans or other pulses can be used instead.

[1] A further simplified technique involves piercing the crust repeatedly with the tines of a fork to produce small holes, allowing steam to escape and preventing the crust from bubbling up, but that does not work with soft doughs such as pâte sucrée.