01 - Preheat oven broiler to high.
02 - Cook macaroni in a large pot of salted boiling water until al dente. Drain and set aside.
03 - In a large oven-safe skillet, heat olive oil over medium heat. Add onion, red bell pepper, and jalapeño (if using). Sauté for 4–5 minutes until softened. Add garlic and cook 1 minute more.
04 - Stir in green chiles, cumin, smoked paprika, chili powder, salt, and black pepper. Cook for 1 minute to bloom spices.
05 - Push vegetables to the side of the skillet. Add butter to the empty side and melt. Stir in flour to make a roux, cooking for 1 minute.
06 - Gradually whisk in milk and bring to a simmer, stirring until thickened (about 3–4 minutes).
07 - Lower heat and add cream cheese, cheddar, and Monterey Jack. Stir until fully melted and smooth.
08 - Add drained macaroni, stirring to combine evenly with sauce and vegetables.
09 - In a small bowl, mix panko with melted butter. Sprinkle evenly over the macaroni mixture in the skillet.
10 - Broil for 2–3 minutes until the topping is golden brown.
11 - Remove from oven, garnish with fresh cilantro if desired, and serve hot.