HEAT oven to 350°F. Line 24 medium muffin cups with paper baking cups. Beat 1/2 cup sugar and cream cheese in large bowl until smooth. Beat in egg until smooth. Stir in chocolate chips; set aside.
BEAT remaining ingredients in large bowl on high speed 3 minutes. Reserve 1 1/2 cups batter.
FILL each muffin cup 1/3 full. Spoon 1 tablespoonful cream cheese mixture onto batter in each cup. Top each cup with reserved batter.
BAKE 30 to 35 minutes or until toothpick inserted in center comes out clean. Cool. Store in Refrigerator.