Preheat oven to 375 degrees.
Scrub potatoes and cut into 1 inch cubes, toss into a bowl. Cut onion and bell pepper into pieces of similar size to the potatoes, and add to the bowl as well.
Add olive oil, Italian seasoning, and garlic powder; toss to coat evenly. Bake in a single layer on a baking sheet for 15 minutes. This will allow veggies and potatoes to begin to soften.
Cut sausage links and mushrooms into 1 inch pieces while potatoes roast.
Remove potatoes from oven and transfer to a bowl. Scrape baking sheet to remove any stuck-on food pieces. Spray with cooking spray.
Skewer potatoes, veggies, sausage, and mushrooms; place onto prepared baking sheet and bake for 25-35 minutes until potatoes have softened and sausage is fully cooked.
Serve pineapple chunks on the side, or skewer them along with other ingredients if desired.