Step 1

Preheat the oven to 425 degrees F (220 degrees C). Line a baking sheet with aluminum foil for easier cleanup and spray with cooking spray.

Step 2

Combine 2 tablespoons olive oil, rosemary, 1/2 teaspoon salt, and 1/4 teaspoon pepper in a large bowl. Add potatoes and toss to coat. Place potatoes skin side-down on the baking sheet in a single layer.

Step 3

Roast in the preheated oven until tender when pierced with a fork, 23 to 25 minutes. Remove from oven; stir.

Step 4

Mix remaining olive oil, salt, pepper, onion flakes, paprika, parsley, and oregano in the same bowl. Add sausage, green beans, bell pepper, and onion; mix until well combined. Add to the baking sheet; spread in a flat layer.

Step 5

Roast until vegetables are tender and potatoes and sausage pieces are browned, tossing halfway through the roasting process, 20 to 25 minutes. Serve immediately.