Heat a tablespoon of olive oil in a skillet over medium heat. Add chopped onion, minced garlic, and diced green and red bell peppers. Sauté for 5 to 7 minutes until softened.

In a large bowl, combine the ground beef, optional ground pork, sautéed veggies, breadcrumbs, cheddar cheese, bacon, sour cream, milk, eggs, Worcestershire sauce, Dijon mustard, and spices. Mix gently.

Bring a pot of salted water to a boil. Add peeled and diced potatoes and cook for 15 to 20 minutes until fork-tender. Drain and return to pot.

Mash the drained potatoes in the pot. Add butter and a splash of milk, then fold in sour cream, cheese, and bacon. Season with salt and pepper.

Preheat oven to 350°F (175°C) and grease a baking dish.

Transfer meat mixture to the baking dish, shape into a loaf, and spread the potato topping over it.

Bake for 60 to 75 minutes until internal temperature reaches 160°F (71°C) and top is golden brown.

Remove from oven and let rest for 10 to 15 minutes before slicing and garnishing with green onions.