Heat the vegetable oil in a large skillet over medium-high heat.
Add the ground beef to the skillet and cook, breaking it up with a spoon, until browned and cooked through, about 5-7 minutes.
Add the chopped onion and minced garlic to the skillet with the beef. Cook until the onion is softened, about 3-4 minutes.
Stir in the ground cumin, chili powder, smoked paprika, dried oregano, salt, and black pepper. Cook for 1 minute until fragrant.
Pour in half of the enchilada sauce and stir to combine. Reduce heat to medium-low and simmer for 3 minutes.
Remove the skillet from heat. Warm the corn tortillas in a microwave or on a dry skillet until pliable.
Spoon about 1/4 cup of the beef mixture onto each tortilla, roll it up tightly, and place seam-side down back into the skillet.
Pour the remaining enchilada sauce evenly over the rolled tortillas in the skillet.
Sprinkle the shredded cheddar and Monterey Jack cheeses evenly over the top.
Cover the skillet with a lid and cook over low heat until the cheese is melted, about 7-10 minutes.
Remove from heat and sprinkle with chopped fresh cilantro.
Serve the skillet beef enchiladas hot, garnished with diced tomato, sour cream, and jalapeño slices if desired.