1Heat oven to 350. Spray 12 muffin cups w/ cooking spray. In lg bowl, stir together flours, sugar, Splenda, baking soda, and baking powder. In another bowl, combine yogurt, egg, vanilla, butter and blueberries. Stir yogurt mix into flour mix, Mix until just combined. Spoon mix into muffin cups, 1/2 way full. Bake 25 min, or until toothpick inserted in center comes out clean.