From YavelWiki

Prep Time: 30 mins; Cook Time: 35-40 mins; Serves: 6

Ingredients

• 1 pound lean ground beef
• 1 1/2 cups diced onion
• 1 1/2 cups (about 2 medium) finely diced zucchini
• 12 corn tortillas, heated or fried in oil to soften
• 2 1/2 cups enchilada sauce, canned or homemade
• 3 cups cheddar- jack shredded cheese
• Serve as desired with: shredded lettuce, avocado, cilantro, sour cream

Instructions

1. Preheat oven to 350 degrees F. Spray a 9x13-inch pan with nonstick spray.
2. Heat oil in a large skillet. Add ground beef; break apart with a spoon or spatula to crumble the meat. Saute the meat on medium heat until browned (about 5 minutes). Tilt the pan and spoon the fat out of the pan; discard. Remove cooked meat to a bowl.
3. Return pan to medium heat and add onion and zucchini. Saute until just softened, 3 to 4 minutes. Remove the vegetables from the pan and add to the meat mixture; set aside.
4. Add 1/2 cup of sauce to the prepared pan. Spread it around so it coats the entire bottom of the pan.
5. Assemble the enchiladas: Place tortilla on a work surface. Spoon 1/4 to 1/3 cup of the meat mixture down the middle. Sprinkle 2 Tablespoons of cheese on top of the meat. Drizzle 1 Tablespoon of sauce on top. Wrap the tortilla around the filling tightly and place it seam-side-down in the pan. Repeat with remaining tortillas and filling until you have finished filling 12 tortillas. Place the tortillas side-by-side in the pan- it's okay if they are all snuggled in there tightly.
6. Pour remaining enchilada sauce over the top of the stuffed enchiladas. Cover the dish with foil and bake for 30 minutes.
7. Remove pan from the oven and take off the foil. Sprinkle remaining cheese on top; return to the oven and let the cheese melt (about 5 minutes).
8. Serve immediately with desired condiments