1. Preheat oven to 350°.
2. Place chicken in a medium saucepan and cover with water. Bring to a boil; cover, reduce heat, and simmer 15 minutes or until tender. Drain chicken, and cool slightly. Shred chicken with 2 forks, and place in a large bowl.
3. Heat oil in a large nonstick skillet over medium-high heat. Add onion; sauté 5 minutes or until tender. Add half of onion to chicken. Place remaining half of onion, 1/2 cup water, and next 6 ingredients in a blender; process until smooth.
4. Add 1/2 cup tomato mixture and cream cheese to chicken mixture. Spread 1/2 cup tomato mixture in bottom of a 13 x 9–inch baking dish coated with cooking spray; return remaining tomato mixture to pan. Heat over low heat until warm; keep warm.
5. Working with 1 tortilla at a time, dip tortilla in warm sauce in pan, coating both sides. Place on a plate; spoon 3 tablespoons chicken filling onto each tortilla; roll up, and place in dish. Spoon remaining sauce over enchiladas in dish. Sprinkle enchiladas with cheddar cheese.
6. Bake, uncovered, at 350° for 30 minutes or until thoroughly heated. Garnish with green onions and cilantro, if desired.
These enchiladas were relatively simple to prepare, and the recipe called for ingredients that I would ordinarily already have in my kitchen, which is great! I might replace the can of mild chili peppers with one or two fresh jalapeño peppers for a bit more spice. —Peggy Christoffer