Here are a couple of tips that I learned while making the pot-pie on the last post. Some also work well when top-crust-only fruit pies.
Who wants soggy dough? Safe to say - no one. And since we know that steam makes pot pie crusts soggy, then it’s time to cheat a little and try this trick which may be a bit unconditional, but you get your bottom dollar you are going to get a nice crispy top crust. Heat the filling separately in the baking dish. Cut a pastry round a bit larger than the dish, to allow for shrinkage, and then bake it, alone until cooked. Set the pastry on top of the filling. This works great if you do individual pot pies.
If you cannot bring yourself to do it this unconventional way, shield the underside of the dough from the steamy filling by brushing it lightly with beaten egg white.
And remember to give your crust something to cling to, so it does not shrink away from the sides. This is a cool trick. Roll strips of dough between your palms. Line the rim of the baking dish with the strips. Drape the top crust over the baking dish. Don’t stretch it. Press the crust into the strips to create a seal; of course this works best with a flat rim-baking dish.
We talked about the crust but what about the wash?
Whisk just to break up the egg; it needn’t be foamy. The salt makes the egg wash smoother and thinner – no white globs.
For a brown glaze – use only the yolk (but watch it, since it tends to burn). For a lighter, firmer, glossier glaze, use just the egg white. For a lovely glow, whisk an egg white with milk. Apply it as the end of the baking time – the last 15 minutes should be ok. And if you want that extra sheen, brush pastry with egg wash, let it dry, then apply a second coat before baking.
And this one I learn the hard way – never slash/score/cut the pastry BEFORE adding the egg wash, otherwise the egg is likely to seal the slashes/score/cut, which in some cases in necessary for rising.