Step 1

In a large skillet, heat the oil over medium heat. Add the onions and bell peppers and cook, stirring occasionally, until soft, about 6 to 8 minutes.

Step 2

Add the beef and break up with a wooden spoon. Cook until no longer pink, about 10 to 12 minutes. If desired, remove the excess grease by tilting the skillet to one side, and remove the grease with a large spoon into a small bowl. Leave about 1 to 2 tbsp in the skillet.

Step 3

Add the beef stock, tomato sauce, chili sauce, Worcestershire sauce, mustard, vinegar, brown sugar, salt, and pepper and bring to a simmer, stirring to fully incorporate.

Step 4

Reduce the heat to medium and simmer for 20 minutes until most of the liquid has reduced down, stirring occasionally.

Step 5

Toast the buttered buns (a couple minutes under the broiler...but keep an eye on them!)

Step 6

On a baking sheet, add a mound of meat mixture for each sandwich you are preparing. Place a handful of cheese on top of each mound of meat. Place under the broiler until cheese has melted. Keep an eye on them, don't let them burn!

Step 7

Use a spatula to transfer the sloppy joe mounds topped with melted cheese onto the bun bottoms. Add the top bun and serve at once!