1/2 c. chopped onion
2 garlic cloves, minced
1 1/2 c. canned Italian tomatoes (with liquid); drain, seed, and chop tomatoes, reserving liquid
1/2 c. sliced mushrooms
1 tsp. each seeded and minced jalapeno or serrano pepper and salt
1/8 tsp. pepper
8 oz. skinned and boned cooked chicken (preferably breasts), chopped
4 corn tortillas (6-inch diameter each)
4 oz. sharp cheddar cheese, shredded, divided
8 pitted black olives, sliced
1/2 c. plain low-fat yogurt

Spray 10-inch nonstick skillet with nonstick coking spray and set over medium heat; add onion and garlic and cook, stirring constantly, about 1 minute. Add tomatoes and reserved liquid, the mushrooms, pepper, and seasonings and cook, stirring occasionally, until sauce is thickened, 5-8 minutes.

Transfer half of sauce to medium heatproof mixing bowl, reserving remaining sauce; add chicken to bowl and mix thoroughly. Set aside. Preheat oven to 375 degrees. Set 8-inch nonstick skillet over medium heat; add 1 tortilla and heat, turning once, just until tortilla becomes flexible, about 1 minute (do not overcook).

Carefully remove tortilla from pan and lay flat; spread 1/2 ounce cheese along center, top with 1/4 of chicken mixture, and roll to enclose. Set seam-side down in 8x8x2-inch baking dish; repeat procedure 3 more times.

Pour reserved sauce over enchiladas, top with remaining cheese, and bake until cheese is lightly browned, 15-20 minutes. Top with olives; serve with yogurt. Makes 4 servings.