Don't even think about baking puff pastry in the microwave or toaster oven. It just doesn't work. Baking temperatures vary. Most pastry chefs agree with the instructions on the box -- bake puff pastry at a high temperature for a short time, usually at 400 degrees for about 20 minutes.When the pastry is high and golden brown, it is done.ere are some tips for working with ready-made puff pastry. Thaw frozen pastry sheets at room temperature for 20 to 30 minutes before gently unfolding. Wrap unused sheets in plastic wrap or foil and return to the freezer. Always preheat the oven prior to baking as directed in the recipe.