In a large skillet over medium heat, add the ground beef. Cook until browned, breaking it apart with a spatula, about 5-7 minutes. Drain excess fat if necessary.

Stir in the chili powder, cumin, garlic powder, onion powder, salt, and pepper. Cook for an additional 2-3 minutes until the spices are fragrant.

Remove the skillet from heat and stir in the cheddar and Monterey Jack cheeses until melted and well combined.

Heat a separate skillet over medium heat and add 1 tablespoon of vegetable oil.

Place one tortilla in the skillet and spread a quarter of the beef and cheese mixture on one half of the tortilla. Fold the other half over to create a half-moon shape. Cook for 3-4 minutes on each side until golden brown and crispy.

Repeat with the remaining tortillas and filling, adding more oil to the skillet as needed.

Cut each quesadilla into wedges and serve warm with sour cream and salsa on the side.