Preheat your oven to 425°F (220°C).
Heat the oil in a large pan or Dutch oven to medium heat and add the onions, jalapeno (if using), and bell peppers. Cook for 10 minutes to soften, stirring often.
Add the garlic and cook 1 minute, or until the garlic becomes fragrant.
Add the ground beef and cook 5-6 minutes, breaking apart as you go, until cooked through.
Add the fire roasted tomatoes, Worcestershire sauce, seasonings, and cooked rice. Stir together and remove from heat.
Stir in half of the shredded cheese until incorporated.
Transfer to a casserole dish or baking dish (or keep in the Dutch oven or other oven safe pan).
Top with the remaining shredded cheese.
Bake the casserole for 15-20 minutes, or until the cheese is nice and bubbly.
Cool slightly, garnish, and serve.