In a blender, combine raspberries, bananas, pineapple and brown sugar; cover and process until blended. Transfer to a small saucepan; cook and stir over low heat until heated through. Set aside and keep warm.
For pancakes, combine the dry ingredients in a bowl. In another bowl, beat the eggs, buttermilk, oil and vanilla. Stir into dry ingredients just until moistened. Pour batter by 1/4 cupfuls onto a greased hot frypan. Turn when bubbles form on top; cook until the second side is golden brown. Serve with warm fruit topping.