Martha and chef Laurent Tourondel make giant cheese popovers.
Place a popover pan with 12 cups in the oven and preheat to 350 degrees.
Sift together flour and salt onto a piece of parchment paper; set aside.
In a small saucepan, heat milk over medium heat until small bubbles form around the edges of the pan. Whisk eggs in the bowl of an electric mixer fitted with the whisk attachment. Slowly add heated milk to eggs, whisking constantly. Gradually whisk in flour mixture.
Remove heated popover pan from oven; spray each cup with nonstick cooking spray and place on a baking sheet. Fill each cup with batter so it is level to the top; top with cheese.
Bake 15 minutes. Rotate pan 180 degrees; continue baking until golden brown, about 35 minutes more.
Invert pan and remove popovers. Serve immediately. Popovers may also be made 2 hours in advance. Cool on a wire rack and reheat in an oven heated to 450 degrees just before serving.