I have seen two methods to counter this. One is the traditional way of pricking the base with a fork, then blind baking at 200C with weights etc. for 10 minutes, then giving an additional 5 minutes without the weights, then add the filling.
The other is to prick the base as before, seal with beaten egg white, place in the freezer for 30-60 minutes, then add the filling.
The latter to me, seems to be a good way of using up the leftover egg white when making the classic custard filling in a quiche, but does it deliver better results than the traditional blind baking method?