Cook and stir onions and garlic in large nonstick skillet on medium heat 5 min. Add meat; cook 8 min. or until evenly browned, stirring occasionally. Stir in 1 can tomato sauce and A.1. Bring to boil. Stir in nuts and raisins; simmer on medium-low heat 5 min., stirring occasionally. Remove from heat.
Pour remaining tomato sauce into 13x9-inch baking dish. Carefully open chiles to flatten; place, bottom sides down, on work surface. Top each with 1 Singles and 1/2 cup meat mixture; roll up, starting at one short end. Place over sauce in baking dish.
Beat egg whites in medium bowl with mixer on high speed until stiff peaks form. Add egg yolks; beat on low speed just until blended. Stir in Parmesan and pepper. Spread evenly over chiles, sealing to all sides of dish.
Bake 30 min. or until top is golden brown and casserole is heated through.