PREHEAT oven to 350°F. Mix flour, brown sugar and 1/2 tsp. of the cinnamon in medium bowl. Cut in butter until mixture resembles coarse crumbs; set aside.
BEAT cake mix, ricotta cheese, eggs, water, oil and remaining 1 tsp. cinnamon in large bowl with electric mixer on low speed just until moistened. Beat on medium speed 2 minutes. Pour into greased and floured 13x9-inch baking pan. Top with apples; sprinkle with the crumb mixture.
BAKE 55 minutes to 1 hour or until toothpick inserted in center comes out clean. Cool completely on wire rack.