Preheat the to 375 degrees F.
Place the potatoes on a baking sheet and bake until fork tender, about 45 minutes.
Place the hot potatoes on a cutting board and dice them into 1-inch pieces.
Heat a skillet over medium-low to medium heat. Next, put a tablespoon of canola oil in the skillet. Add in some butter and the onions and saute until they start to turn brown. Next, throw in the cooked diced potatoes and the peppers. Salt and pepper the potatoes, then stir them around, slightly pressing/packing them in the skillet. Cook without stirring for 5 to 7 minutes. You want to make sure the pan is hot enough to crisp the potatoes. Add more butter to the pan as necessary for moisture.
After several minutes, use a spatula to flip the potatoes over and cook on the other side for another 5 to 7 minutes.