Preheat the oven to 350°F and spread 1/2 cup of the enchilada sauce on the bottom of a 9x13-inch baking dish.

If your tortillas are too stiff to roll without cracking, wrap them in a damp towel and warm them for a few seconds in the microwave.

In a small bowl, mix together 3/4 cup of the cheddar cheese and 3/4 cup of the Jack cheese.

Fill a tortilla with some of the cheese blend and some of the Oaxaca cheese, black beans, and spinach. Roll the tortilla closed and place it seam side down in the prepared baking dish. Repeat with the remaining tortillas. Pour the remaining 1 cup sauce on top of the enchiladas, leaving the edges of the tortillas bare, if desired. Top with the remaining 1/2 cup cheddar cheese and 1/2 cup Jack cheese.

Bake, uncovered, for 20 minutes, or until the cheese is melted and the edges of the tortillas are crisp. Remove from the oven and let cool slightly, then top with jalapeño slices, cilantro, avocado, and squeezes of lime and serve.