Mix the flour, sugar, baking soda, baking powder together set aside.Mix together the buttermilk, ricotta cheese, vanilla, and eggs set aside.Now mix together the dry mixture and wet mixture just until blended.Add the melted butter to the mixture. Blend the mixture just until blended.Gently fold (mix) the blueberries into the waffle mixture.Cook waffles according to your waffle maker's instructions.