- Preheat waffle baker according to manufacturer’s directions.
- Place oats in food processor and process until finely ground. Whisk together oats, all purpose flour, whole wheat flour, cornmeal, baking powder, baking soda, and salt in large bowl. Whisk together banana, egg, milk, yogurt, oil, and vanilla in another bowl. Add banana mixture to flur mixture, stirring just until blended.
- With electric mixer on high speed, beat egg whites in medium bowl until stiff peaks form. With rubber spatula, gently fold beaten whites, one-third at a time, into batter, stirring just until blended.
- When waffle baker is ready, spray with nonstick spray. Pour enough batter for 1 waffle onto center and quickly spread to within 1 inch of edges. Close baker and bake as manufacturer directs. Repeat, reheating and spraying waffle baker with nonstick spray before adding each batch of batter.
- Meanwhile, to make the sauce, place 1 cup strawberries in large bowl. Add sugar and crush berries with potato masher or fork. Slice remaining strawberries and add to bowl. Stir in blueberries and lemon zest. To serve, top each waffle with about ½ cup berry mixture. Sauce may be stored refrigerated in an airtight container overnight.
- Per serving (1 waffle and ½ cup sauce)
To freeze the waffles, arrange in a single layer on a wax paper lined baking sheet and place in the freezer until frozen, about 2 hours. Transfer to a zip-close plastic bag and freeze up to 2 months.