peel, cinnamon and salt in large bowl. Make well in center. Add milk, butter and egg to well and mix until smooth. Fold in berries. Spoon batter into prepared tin, filling cups 2/3 full. Top each with 1 heaping tablespoon streusel. Bake muffins until tester comes out clean, 20 to 25 minutes. Cool 5 minutes in tin on rack. Remove muffins from tin. Serve warm or at room temperature. *