Preheat oven to 400 degrees F/200 degrees C. With nonstick cooking spray, spray muffin cups of a 9 to 12 muffin tin. Place paper liners in each cup, spraying the paper liners also.
In a large bowl, combine flour, cornmeal, sugar, baking powder, baking soda, salt and zest.
In another bowl, beat milk, eggs, oil and vanilla extract with a whisk for 1 minute. Pour wet ingredients into dry and stir with a large spatula until moistened, using no more than 15-20 strokes. Gently fold in raspberries, taking care not to break them up. Batter will be lumpy.
Spoon batter into each paper-lined muffin cup until just level with top of the pan. Bake in center of the oven until tops are browned and feel dry and springy, and a cake tester inserted into the center comes out clean, about 25 minutes. Do not overbake.
Let muffins rest in pan for 5 minutes before turning them out onto a rack to cool. Serve immediately or freeze in plastic bags for up to 3 months.
Makes 9-12 muffins.
Date: September 8, 2006