1 cup all-purpose flour (about 4 1/2 ounces) 3/4 cup whole wheat flour (about 3 1/2 ounces) 1/4 cup granulated sugar 1/4 cup packed dark brown sugar 1 tablespoon baking powder 1/2 teaspoon salt 1 1/4 cups fat-free milk $ 1/3 cup creamy peanut butter 1/4 cup egg substitute 2 tablespoons butter, melted $ 1 teaspoon vanilla extract Cooking spray $ 1/4 cup strawberry jam

Preheat oven to 400°.
Lightly spoon flours into dry measuring cups; level with a knife. Combine flours, sugars, baking powder, and salt in a large bowl; stir with a whisk. Make a well in center of mixture. Combine milk and next 4 ingredients (through vanilla); add to flour mixture, stirring just until moist.
Spoon batter into 12 muffin cups coated with cooking spray. Fill each cup half full with batter. Spoon 1 teaspoon jam into each cup. Spoon remaining batter on top to cover jam. Bake at 400° for 20 minutes or until muffins spring back when touched lightly in center. Let cool in pan 5 minutes. Remove from pan, and cool on a wire rack.