烤箱预热至摄氏175度（华氏350度）。 自制双层蒸锅。 烤布丁。

I'm interested in that, but I only have a few mins. Can you give me at most the first 500 characters of a detailed explanation in English about that?
A bain marie is a water bath that helps the flan cook evenly and prevents it from cracking by creating a humid environment in the oven. To make one, pour hot water into a large, wide pan into which you can fit the baking dish or ramekins. Set the baking dish or ramekins into the water bath.  Make sure the water isn't so deep that it rises up the sides of the baking dish or ramekins. You don't want water to get into your flan. A roasting pan makes a good bain marie pan. Lower the bain marie caref