This is a test of commonsense. Complete the next sentence:

How to make mascarpone
Fill the bain marie with water, and place on a stove top over high heat.
Gas stoves work best. As the pans and water heat up, you may reduce and readjust the heat.
Add 1 quarter of heavy cream to the top of the bain-marie. Heat, stirring constantly, to a steady temperature of about 180 degrees f (about 82 c).