Success with popovers is easy with these tips:
In order for popovers to reach the maximum height while baking, all ingredients should be brought to room temperature before mixing.
Place the oven rack in the lowest position.
Generously grease the popover pan cups.
Don't open the oven door while baking or the popovers will fall.
After removing popovers from the oven, prick the tops with the point of a sharp knife, allowing steam to escape.