Preheat the oven to 400ºF.

Lightly spray 9x13-inch baking dish with cooking spray and set aside.

Heat the olive oil in a large skillet over medium-high heat. Saute the onion and bell pepper for 4-5 minutes or until they soften.

Add the ground beef to the pan and cook for 6-8 minutes or until the beef is browned and cooked through. Drain excess grease if necessary.

Add the tomato paste and garlic. Cook 1 minute or until fragrant.

Add the broth, ketchup, Worcestershire sauce, mustard, salt, and pepper, and stir to combine. Bring to a gentle boil, then reduce the heat to low and simmer for 5 minutes.

Spread the sloppy joe sauce into the bottom of the prepared baking dish.

Top with a single layer of tater tots and bake for 25 minutes or until the tater tots are golden brown.

Sprinkle the cheese over the top. Bake for another 5-10 minutes or until the cheese has melted.

Allow the casserole to rest for 5 minutes before serving.