Turn the oven on to 400°F. Make sure the rack is in the middle of the oven. Grease the insides of 6 popover containers with a little piece of butter, using your fingers or a piece of paper towel.

Crack 3 eggs into a mixing bowl. Bear the eggs briskly with a whisk, just until the yolks and whites become all yellow. (Beating is more vigorous than stirring and you do it very fast.)

Add the 1 cup and stir until the eggs and milk are mixed together.

Add the 1 cup flour and ½ teaspoon salt to the egg mixture in the bowl and beat the batter with the whisk until it is smooth and the lumps have disappeared.

Pour the popover batter into a 4-cup measuring cup or pitcher, so it’s easy for you to pour the batter into the popover containers.

Fill each popover container about half full of batter.

If you are using individual Pyrex cups, place them 2 inches apart on a baking sheet and put the baking sheet into the center of the oven. Or put the popover pans in the oven.

Set the kitchen timer for 25 minutes. When the timer bell goes off, start checking the popovers. Popovers bakes in Pyrex cups usually take about 25 to 35 minutes. They should stand tall and be puffed up, looking like giant golden balloons. When they are nice and brown on top, they are done.

When the popovers are done, remove them from the oven with pot holders. Quickly pierce each popover in 3 or 4 places around the top and sides with the pointed tip of a paring knife. The holes let the steam escape, which helps prevent the popovers from falling, or flattening out. (By doing this trick of piercing the popovers quickly, you can reheat them, if you don’t eat them all up at once, and they will again puff up a little.) Remove the popovers from their pan or cups. If they don’t come out easily, run a knife around the sides of each popover. Eat them hot with butter and strawberry jam.