1. Preheat the oven to 375°F, grease a muffin pan with the non-fat cooking spray, and bring a large pot of salted water to boil.
2. In a large bowl, combine the ground beef, breadcrumbs, cheese, milk, ¼ cup of the ketchup, onions, bell peppers, garlic powder, oregano, salt, black pepper, and the egg.
3. Once the beef mixture is well combined, divide it evenly into 10 of the muffin tin indentations.
4. In a small bowl, combine the remaining ketchup and mustard.
5. Once the sauce is fully mixed together, spoon a little on each mini meatloaf, and then place them in the hot oven to cook for 20 to 25 minutes.
6. Once the mini meatloafs are cooked, remove them from the oven and let them cool while you make the mashed potatoes.
7. Place the mini potatoes in the pot of boiling salt water and let them boil for 10 to 20 minutes, until they can be easily pierced with a fork.
8. Once the potatoes are super soft, drain them, put them back in the pot, add the butter, and then mash them with a potato masher or blend them with a hand blender until smooth.
9. Once the potatoes are fully mashed, add a little to the top of each mini meatloaf.
10. Once the mini meatloafs are cooled and topped with potatoes, put 2 in 5 different air-tight containers, and store them in the fridge.
11. When ready to enjoy a serving, a set of 2, remove them from the fridge, heat them up in the microwave for a few minutes, and then dig in!