How to Make It
Preheat oven to 425°F. Stir together potatoes, bell pepper, onion, garlic, salt, pepper, and 2 tablespoons of the oil on a large rimmed baking sheet until evenly coated, push mixture to 1 side. Place sausages on other side of baking sheet. Bake in preheated oven 25 minutes.
Whisk together mustard, honey, and remaining 1 tablespoon oil in a small bowl; spoon over sausages. Continue baking until vegetables are tender and a thermometer inserted in sausage registers at least 160°F, about 5 minutes. Increase oven temperature to broil, and broil until light golden brown, about 3 minutes. Sprinkle with parsley.