01 - Cook the elbow macaroni according to package instructions until al dente. Drain well and set aside.
02 - In a large skillet or Dutch oven, heat the olive oil over medium heat. Add the chopped onion and sauté for 3 minutes until softened and translucent.
03 - Stir in the minced garlic and diced red bell pepper. Continue sautéing for another 2 minutes until fragrant.
04 - Add the ground beef to the skillet, breaking it apart with a wooden spoon. Cook until thoroughly browned with no pink remaining, then drain off any excess fat.
05 - Season the beef with chili powder, ground cumin, smoked paprika, salt, and black pepper. Stir and cook for 1 minute to bloom the spices and release their aromatics.
06 - Stir in the tomato paste, diced tomatoes, drained kidney beans, and beef broth. Mix thoroughly and bring the mixture to a simmer.
07 - Reduce the heat to medium-low and let the chili simmer uncovered for 10 minutes, allowing the flavors to meld and the sauce to thicken.
08 - Fold in the cooked macaroni, milk, shredded cheddar cheese, and half of the mozzarella. Stir continuously until the cheeses are fully melted and everything is evenly coated.
09 - Sprinkle the remaining mozzarella over the top. Cover the skillet and let it rest off the heat for 2 to 3 minutes until the cheese melts, or place under the broiler for a golden, bubbly crust.
10 - Serve hot, garnished with additional cheese or fresh herbs as desired.