In a small bowl, whisk together flour, baking powder, salt, and sugar; set aside.
In a large bowl, whisk together eggs, milk, and 2 tablespoons melted butter until combined. Stir in dry ingredients. Mixture should be lumpy—do not overmix.
Put ebelskiver pan over medium high heat. Add ¼ teaspoon butter to each well of the mold and, when bubbling, add 1 tablespoon of batter. Top each well with 1 teaspoon of jam and sliced strawberries then top with another 1 tablespoon batter.
Let ebelskivers cook until bottoms are golden, about 4 minutes, then flip and continue to cook until tops are also golden, 3 minutes more.
Transfer to a plate . Repeat with rest of batter, then serve immediately with confectioners' sugar on top or maple syrup.
