German Pancake

6 large eggs
1 cup 2% milk
1 cup all-purpose flour
1/2 teaspoon salt
2 tablespoons butter, melted
buttermilk syrup:
1/2 cup butter, cubed
1-1/2 cups sugar
3/4 cup buttermilk
2 tablespoons corn syrup
1 teaspoon baking soda
2 teaspoons vanilla extract
Confectioners’ sugar
Fresh blueberries, optional

Preheat oven to 400°. Place first 4 ingredients in a blender; process just until smooth.
Pour melted butter into a 13x9-in. baking dish; tilt dish to coat. Add batter; bake, uncovered, until puffed and golden brown, about 20 minutes.
Meanwhile, place butter, sugar, buttermilk, corn syrup and baking soda in a small saucepan; bring to a boil. Cook, uncovered, 7 minutes. Remove from heat; stir in vanilla.
Remove pancake from oven. Dust with confectioners’ sugar; serve immediately with syrup and, if desired, fresh blueberries.