Cream puff is always concave at the bottom?

"Cream puff is always concave at the bottom??"

I have had this happen in my own kitchen here in Canada, and it is almost always the same cause. The shells look done, but inside they are still steamy.

Underbaked steamy shells cave in as they cool. The steam inside softens the base, the bottom sinks in, and you get that concave dip instead of a flat base that sits properly.

The fix is to bake them longer than you think. Bake deep golden and firm, not pale and soft, so the shells are fully set before they come out.

At the very end, once the shells are deep golden, firm and fully set, pierce each one, side or bottom, and dry them for 10 minutes in a low oven before filling. That lets the steam out and dries the inside, so the bottoms stay firm and flat and hold the filling instead of sinking under it.

Asked on r/Baking

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