Mix the potatoes with garlic powder, paprika, salt and pepper, and half of the olive oil in a bowl. Place on a foil lined baking sheet and cook in the oven for 20 minutes.
Add the sausage to the pan and then flip the potatoes using a spatula. Cook for 10 minutes and then flip the sausage and cook to an internal temperature of 155 degrees using a thermometer.
In the meantime in a nonstick pan heat the remaining oil on medium heat; saute the onion and pepper for 6 - 10 minutes, or until they are soft and golden brown.
Slice the sausage into chunks and miix with the potatoes, onions, and peppers. Serve with crusty bread and mustard if desired.