Batter:
Mix flour, baking powder, salt and sugar together in
a medium bowl.
Add
the milk, vanilla, and melted butter, and stir to blend.
Pour
into an ungreased 8 inch square baking dish.
Sauce:
Mix the white and brown sugars together. Sprinkle evenly
over top of the batter.
Evenly
pour the orange juice over top of all.
Bake
at 350 degrees F. for about 35 minutes. Serve warm.