In a large high-walled skillet, heat the olive oil over medium heat. Add the lean ground beef, chopped red bell pepper, and minced garlic. Cook while stirring regularly and breaking up the meat until the beef is browned and cooked through (reaching 165˚ F).

Sprinkle in the onion powder and dried Italian herbs. Add the spicy tomato sauce and beef broth to the skillet. Stir everything together to combine, and bring the mixture to a gentle simmer. This will help meld the flavors and create a savory base for the pasta.

Add the elbow macaroni to the simmering skillet, stirring thoroughly so it's well-incorporated. Continue to cook the mixture uncovered for about 10 minutes, or until the macaroni is tender. Taste and adjust seasoning with salt and pepper as needed. I always check the pasta for doneness a minute early so it doesn't overcook.

When the macaroni is cooked, stir in about two-thirds of the grated sharp cheddar and low-moisture mozzarella until melted and creamy. Turn off the heat, sprinkle the remaining cheeses evenly over the top, and cover the skillet. Let the dish rest for 5 minutes to allow the cheese to melt and everything to settle together.

Uncover the skillet and scoop the cheesy beefy macaroni onto plates or into bowls. Top each serving with a generous sprinkle of fresh chives for a pop of color and flavor. I find the fresh chives add a lovely brightness at the end.