In a large bowl, whisk together the flour, oats, baking powder, cinnamon, and salt until combined.
Whisk in the eggs, milk, yogurt, oil, puree and brown sugar into the flour mixture until all ingredients are combined. Let stand for 10 minutes while you pre-heat your waffle maker.
If your batter is too thick, add in an additional 1-2 tablespoons of milk.
Pour in roughly 2 tablespoons batter onto lightly greased waffle maker for baby size waffle or 1/4 cup batter for toddler size waffle. Shut lid and cook based on your waffle makers directions. Lift waffle out with fork, slightly cool. Serve or freeze.