Preheat oven to 350F. In a medium-sized bowl, whisk together dry ingredients: flour, sugar, baking powder, and baking soda.
In a separate bowl, beat together the wet ingredients: apple sauce, yogurt, egg, milk, and vanilla.
Slowly whisk the wet ingredients into the dry until just fully combined. Fold in sprinkles, reserving about a tbsp or so to sprinkle on top.
Evenly divide batter between 9 donut molds or muffin tins. Mine came out to about 3 tbsp of batter per mold.
Bake until just cooked through, when a tooth pick inserted comes out clean, about 12-15 minutes. Mine were perfectly done at 13 minutes. Try not to over bake! Let cool for about 5 minutes.