Whole Wheat Apple Muffins

• 1 cup (4 ounces) whole wheat flour
• 1 cup (4 1/4 ounces) all-purpose flour 1 teaspoon baking powder
• 1 teaspoon baking soda
• 1/4 teaspoon salt
• 1 tablespoon cinnamon
• 1/2 cup (1 stick, 4 ounces) unsalted butter, at room temperature
• 1/2 cup (3 1/2 ounces) granulated sugar
• 1/2 cup dark brown sugar, packed, divided
• 1 large egg, lightly beaten
• 1 cup (8 ounces) buttermilk or yogurt
• 2 large apples, peeled, cored, and coarsely chopped

Preheat the oven to 450°F. Grease and flour 18 muffin cups and set aside.

Mix together the flours, baking powder, baking soda, salt, and cinnamon, and set aside. In a separate bowl, cream the butter and add the granulated sugar and 1/4 cup of the brown sugar. Beat until fluffy. Add the egg and mix well; stop once to scrape the sides and bottom of the bowl.Mix in the buttermilk gently. (If you over-mix, the buttermilk will cause the mixture to curdle.) Stir in the dry ingredients and fold in the apple chunks.

Divide the batter evenly among the prepared muffin cups, sprinkling the remaining 1/4 cup brown sugar on top. Bake for 10 minutes, turn the heat down to 400°F, and bake for an additional 5 to 10 minutes, or until a toothpick inserted into the center of a muffin comes out clean. Cool the muffins for 5 minutes in the tin, then turn them out onto a wire rack to cool completely.

Yield 12-18.

VERDICT:  I did, in fact, overmix the buttermilk, and the batter curdled.  The brown sugar also melted, ran right off of the muffins and burned up on the top of the pan and the sides of the muffins.  The smoke detector went off and half the muffins taste like charcoal.  Toss.