01 - Heat olive oil in a large skillet over medium heat. Add the chopped onion and diced red bell pepper, sautéing for 2 to 3 minutes until softened.
02 - Incorporate minced garlic and cook for 30 seconds until fragrant.
03 - Add ground beef to the skillet, breaking it up with a spoon. Cook for 5 to 7 minutes until browned and fully cooked. Drain excess fat if needed.
04 - Stir in ground cumin, chili powder, smoked paprika, salt, and black pepper. Cook for an additional 2 minutes, stirring to combine. Remove from heat and set aside.
05 - Preheat a clean large skillet or griddle over medium heat.
06 - Place one tortilla on the skillet. Sprinkle 1/4 cup each of shredded cheddar and Monterey Jack cheese evenly over the tortilla. Distribute about one-quarter of the beef mixture over the cheese. Add cilantro if desired.
07 - Top with a second tortilla. Cook for 2 to 3 minutes until the bottom is golden and the cheese begins to melt. Flip carefully and cook for another 2 minutes until golden and crispy.
08 - Repeat the assembly and cooking process with the remaining tortillas and filling.
09 - Cut quesadillas into wedges and serve immediately with optional sour cream, salsa, and guacamole.