1Heat oven to 350°F. Spray bottom only of 8-inch square pan with cooking spray. In small bowl, mix all streusel ingredients with fork until crumbly; set aside.
2In large bowl, mix all coffee cake ingredients with spoon just until flour is moistened. Spread half of the batter in pan. Sprinkle with half of the streusel. Drop remaining batter by spoonfuls over streusel; carefully spread over streusel. Sprinkle with remaining streusel.
3Bake 35 to 45 minutes or until toothpick inserted in center comes out clean. Cool 15 minutes. Serve warm.