Cinnamon Swirl Coffeecake Muffins

1/2 cup packed dark brown sugar
1 1/2 teaspoons ground cinnamon
1 cup granulated sugar
1/4 cup butter, softened
1/2 cup egg substitute
1 cup reduced-fat sour cream
2 tablespoons water
1 teaspoon vanilla extract
1 3/4 cups all-purpose flour (about 7 3/4 ounces)
1 teaspoon baking powder
1/2 teaspoon baking soda
1/2 teaspoon salt
Cooking spray
6 tablespoons powdered sugar
3 teaspoons fresh orange juice
Dash of salt

Preheat oven to 400°.

Combine first 3 ingredients; set aside.

Place granulated sugar and butter in a large bowl; beat with a mixer at medium speed until well blended (about 3 minutes). Add egg substitute; beat 3 minutes. Beat in sour cream, water, and vanilla.

Lightly spoon flour into dry measuring cups; level with a knife. Combine flour, baking powder, baking soda, and salt in a large bowl, stirring well with a whisk. Make a well in center of mixture; add sour cream mixture. Stir just until combined.

Place 3 tablespoons brown sugar mixture in a small bowl; set aside. Sprinkle surface of batter with remaining brown sugar mixture. Gently fold batter 4 times.

Place 18 paper muffin cup liners in muffin cups; coat liners with cooking spray. Spoon batter into prepared cups. Sprinkle batter evenly with reserved brown sugar mixture. Bake at 400° for 25 minutes or until a wooden pick inserted in center comes out clean. Remove muffins from pan immediately; place on a wire rack. Cool 10 minutes.

Combine powdered sugar, juice, and dash of salt in a small bowl, stirring until smooth. Drizzle powdered sugar mixture evenly over muffins.

--Adapted from Cooking Light Magazine