Blueberry Upside Down Cake
INGREDIENTS4 tablespoons butter, melted, plus more for souffle dish1/3 cup plus 3 tablespoons light-brown sugar1 1/2 cups blueberries, picked over and cleaned3/4 cup cake flour (not self-rising)1 teaspoon baking powder1/4 teaspoon salt1 large egg1/4 cup milk, room temperatureDIRECTIONSHeat oven to 3…