In a sauté pan melt the butter over medium high heat. Add in the sliced peaches and sauté for a minute. Add in the bourbon, brown sugar, and vanilla and sauté another 2 minutes or until the peaches have caramelized slightly and the sauce has thickened.

In a small saucepan over medium heat melt the butter. Continue to heat the melted butter until it starts to foam. Stir the foamy butter until the foam subsides and starts to brown. Once the butter is a caramel color remove it from the heat and pour it in a small dish to cool.

In a mixing bowl whisk together the whole wheat flour, salt, cinnamon, sugar, and baking soda. In another bowl whisk together the buttermilk, egg yolk (save the egg white in another bowl), cooled brown butter, and vanilla extract. Add the wet ingredients into the dry and fold together until combined.

Using a stand mixer, hand mixer, or a whisk, whisk the egg white until stiff peaks form, about 2-4 minutes. Gently fold the egg white into the waffle batter being careful not to deflate it.

Using a 1/2 cup measuring cup, scoop out the batter and add it to a heated and greased waffle iron. Cook the waffle until golden brown and crispy.

Spoon the bourbon peaches over the waffle and top with butter and maple syrup if desired.