Crispy Oven-Roasted Rosemary Chicken with Sausage and Potatoes

Preheat oven to 450 degrees F (230 degrees C). Prepare a large baking dish with cooking spray.
Pour half of the olive oil into a large skillet over medium heat. Cook the bratwurst in the hot oil until browned on both sides, about 5 minutes; set aside. Add the remaining olive oil to the skillet and return to heat; brown the chicken pieces in the hot oil 7 to 10 minutes; season with salt while cooking; set aside and return the skillet to heat. Heat the potatoes in the skillet until lightly browned. Arrange potatoes, chicken, and bratwurst in the prepared baking dish; season with salt and drizzle with 2 tablespoons olive oil; sprinkle with about half of the chopped rosemary.
Roast in the preheated oven 15 minutes. Turn each piece of chicken over and stir the potatoes and sausage. Sprinkle the remaining rosemary and the red wine vinegar over the dish; cook another 15 minutes.