Scalloped potatoes and ham

4-1/2 lb. red potatoes (about 9), cut into 1/4-inch-thick slices
1 container (16 oz.) Sour cream
3/4 lb. (12 oz.) VELVEETA 2% Milk Pasteurized Prepared Cheese Product, cut into 1/2-inch cubes
1/2 lb. (1/2 of 1-lb. pkg.) OSCAR MAYER Smoked Ham, chopped
4 green onions, sliced
1/4 cup KRAFT Grated Parmesan Cheese


HEAT oven to 350°F.

COOK potatoes in boiling water in large covered saucepan 10 to 12 min. or just until potatoes are tender; drain. Remove 3/4 of the potatoes; place in large bowl. Add sour cream; mash until smooth. Stir in VELVEETA, ham and onions. Gently stir in remaining potato slices.

SPOON into 13x9-inch baking dish sprayed with cooking spray; sprinkle with Parmesan.

BAKE 30 min. or until heated through.