Preheat oven to 400F and line baking sheet with parchment paper.
Using a skillet, add 1 lb ground beef and 1 small chopped onion. Saute over medium high heat, stirring few times and breaking the meat into small pieces with a wooden spoon. Saute until ground beef is browned, about 7-10 minutes. Drain grease.
Next, add 2 cloves of finely chopped garlic, 2 teaspoons of taco seasoning, salt and pepper to taste. Give it a good stir with a spoon. Stir in 4 oz. of green chilies and 16 oz. refried beans until well blended. Turn off heat, cover with a lid.
Place warm tortilla on a plate and add about a 1/2 cup of the ground beef mixture onto the center. Add Cheddar Jack cheese and chopped spinach.
Now, fold left and right side of the tortilla over the filling, then fold in top and bottom sides of the tortilla over the filling forming a chimichanga.
Brush top of chimichanga with melted butter and bake for 15-20 minutes or until top of chimichangas turn golden brown color.
Serve Beef Chimichangas with salsa, cubed tomatoes, cheese, chopped spinach, sour cream and finely chopped chives. Enjoy!