Heat olive oil in a large skillet over medium-high heat.
Add diced onion and cook until softened, about 3 minutes.
Add minced garlic and cook for 30 seconds until fragrant.
Add ground beef to the skillet and cook, breaking it apart with a spoon, until browned and cooked through, about 6-8 minutes.
Drain excess fat from the skillet if necessary.
Stir in ground cumin, chili powder, smoked paprika, dried oregano, salt, and black pepper. Cook for 1 minute to toast the spices.
Pour in the enchilada sauce and stir to combine.
Add black beans and corn to the skillet, stirring until evenly mixed and heated through, about 3 minutes.
Sprinkle shredded cheddar and Monterey Jack cheese evenly over the beef mixture.
Cover the skillet with a lid and reduce heat to low. Cook until cheese is melted, about 3-4 minutes.
Remove skillet from heat and garnish with sliced green onions, chopped cilantro, diced tomato, and diced avocado.
Serve with lime wedges on the side for squeezing over the skillet.