In a medium bowl, mix the all purpose flour, whole wheat flour, baking powder, sugar, cinnamon, and kosher salt until thoroughly combined.
In another bowl, whisk the oil, oat or almond milk, and vanilla. Pour the wet ingredients into the dry ingredients and mix gently until the batter is mostly smooth.
Immediately, add the batter (1 1/4 cups for a Belgian waffle maker and a little over 1/2 cup for a standard waffle maker) into the center of the waffle iron, then cook according to the waffle iron’s instructions. Remove the cooked waffles and place them on a baking sheet without stacking. Make the waffles to order, or place cooked waffles in a 250°F oven to keep warm.
Cooked waffles can be frozen; place them in a plastic bag and remove the remaining air with a straw before sealing. To reheat, remove from the freezer and lightly toast in a toaster.