Preheat the oven to 400°F (200°C).
In a large bowl, toss the halved baby red potatoes with olive oil, garlic powder, dried Italian seasoning, salt, and black pepper until evenly coated.
Spread the seasoned potatoes in a single layer on a baking sheet.
Place the turkey sausage links on the same baking sheet with the potatoes, spacing them evenly.
Roast in the preheated oven for 25 to 30 minutes, turning the sausage and stirring the potatoes halfway through cooking, until the sausages are cooked through and the potatoes are golden and tender.
While the sausages and potatoes roast, bring a large pot of salted water to a boil.
Add the trimmed green beans and cook for 3 to 4 minutes until tender-crisp.
Drain the green beans and immediately transfer them to a bowl of ice water to stop the cooking process. Drain again and set aside.
In a large skillet, melt the unsalted butter over medium heat.
Add the minced garlic and sauté for 30 seconds until fragrant.
Add the cooked green beans to the skillet and sauté for 3 to 4 minutes, stirring occasionally, until heated through and coated with garlic butter.
Season the green beans with salt and black pepper to taste.
Serve the roasted turkey sausage links alongside the roasted potatoes and sautéed green beans.