Preheat the oven to 425 degrees F. Line a large baking sheet with foil or parchment paper.
Wash and scrub the baby potatoes. Cut into chunks if needed, so they are all about the same size. Lay out in a single layer and pat dry.
To a large bowl, add the potatoes, bell peppers, mushrooms, red onion and garlic. Drizzle with 3 tablespoons olive oil and 3 teaspoons Italian seasoning and toss to coat evenly.
Add the green beans to a medium sized bowl and drizzle with a teaspoon of olive oil and half a teaspoon each of salt and Italian seasoning. Toss to coat evenly. Set aside.
Arrange sausages on the baking sheet and surround with the prepared vegetables. Bake for 15 minutes. With a spatula, scooch the sausages and veggies around a little, but don’t toss them. Add the green beans (nestle them in or just arrange them on top). Bake for an additional 10 minutes, or until sausages are cooked through to 165 degrees F.
Garnish with fresh minced parsley and serve with rice, mashed potatoes or your favorite pasta.
Storage: Place leftovers in an airtight container within 2 hours of cooking. Store in the fridge for up to 3-4 days.Freezing: I don't typically recommend freezing cooked vegetables like this because they tend to become soggy when you reheat. The sausages will freeze nicely; just thaw before reheating.Reheating: Ideally I recommend reheating in a skillet on the stovetop with a little bit of butter. But you can also reheat in the microwave.