Start by placing the milk and melted butter in a microwave-safe bowl. Heat them on high for about two minutes, or until the mixture is warm to the touch. This warmth is crucial for activating the ingredients later.
While the milk mixture cools slightly, sift together the flour, sugar, salt, and baking powder in a large mixing bowl. This step is essential to incorporate air and ensure a light batter.
In another large bowl, crack the eggs and whisk them using an electric mixer on medium speed for about three minutes. You’ll want to see the eggs become foamy and pale in color.
Reduce the mixer speed to low and gradually add the warm milk mixture. This prevents cooking the eggs and helps them blend smoothly.
Slowly add the sifted flour mixture to the wet ingredients while mixing on low speed, beating for about two minutes until just combined.
Let the batter rest for about one hour at room temperature. For best results, refrigerate the batter overnight and take it out at least thirty minutes before baking.
If you’re using a regular popover pan, preheat the oven to 450°F (232°C). Generously spray the pan with nonstick cooking spray to ensure easy release.
Fill each popover cup almost to the top with batter, ensuring they have room to rise. Place the pan on a cookie sheet to catch any overflow.
Transfer the pan to the oven and bake for the first fifteen minutes at 450°F (232°C). This high heat is crucial for the initial rise.
After fifteen minutes, reduce the oven temperature to 375°F (190°C) and continue baking for an additional thirty to thirty-five minutes until the popovers are a beautiful golden brown. If using a petite popover pan, bake at 350°F (176°C) for about forty minutes.
While the popovers are baking, prepare the strawberry butter by placing the softened butter and strawberry preserves in a bowl. Beat until smooth and fluffy, then set aside.
Once the popovers are golden brown, remove them from the oven and let them cool slightly before serving with the strawberry butter.