Cook and stir onions and garlic in large skillet on medium-high heat 3 min. Add ground beef; cook 10 min. or until done, stirring occasionally. Stir in tomato sauce; cook 5 min. Add apples, bacon, raisins and nuts; mix well. Cook 5 min., stirring frequently. Remove from heat; cool completely.
Heat oven to 400°F. Unroll pie crusts on lightly floured surface; cut each into 8 wedges. Use rolling pin to stretch each wedge, 1 at a time, to make 1 inch larger. Spoon about 1/4 cup meat mixture onto center of each wedge; top with Singles piece. Fold dough in half to completely enclose filling; press edges together to seal.
Place on parchment-covered baking sheet; brush with egg.
Bake 20 min. or until golden brown.