01 - Preheat your oven to 375°F. Lightly grease a 9x13-inch baking dish.
02 - In a large skillet, warm olive oil over medium heat. Add the chopped onion, diced bell pepper, and minced garlic; sauté until vegetables soften, approximately 4 minutes.
03 - Add the ground beef to the skillet and cook until it is thoroughly browned, breaking the meat apart as it cooks. Drain any excess fat if necessary.
04 - Stir in the chili powder, ground cumin, smoked paprika, salt, and black pepper. Continue cooking for 1 minute, allowing the spices to become fragrant.
05 - Incorporate the tomato paste, diced tomatoes, tomato sauce, and chili beans into the skillet. Bring the mixture to a simmer and cook for 8–10 minutes, stirring occasionally. Adjust seasonings to your preference.
06 - Arrange the hot dog bun halves, cut side facing up, in the prepared baking dish. Evenly distribute the sliced hot dogs over the buns.
07 - Pour the prepared chili mixture evenly over the hot dogs and buns in the baking dish.
08 - Sprinkle both the shredded cheddar and mozzarella cheeses generously over the top of the chili layer.
09 - Bake the casserole, uncovered, for 20–25 minutes, or until the cheese is beautifully melted and bubbly.
10 - Allow the casserole to cool for 5 minutes before slicing and serving.