In a medium mixing bowl, combine the flour, cornstarch, baking powder, baking soda, salt and sugar.  Whisk together to blend.

In another mixing bowl, beat together the whole milk, buttermilk, oil, egg and vanilla.  Add the dry ingredients to the bowl with the wet ingredients and whisk just until incorporated and few lumps remain.  Set aside to rest for 30 minutes.

Preheat a waffle iron.  Fill waffle wells and cook according to the manufacturer’s instructions.  Cook until crisp and golden.  Serve immediately. Yield: depends on the size/shape of your waffle iron.  I doubled the recipe and got 4 1/2 Belgian waffles.