Drizzle 1 1/2 tablespons olive oil on a large baking sheet. Add sweet potatoes and arrange in a single layer. Evenly add onions, mushrooms, bacon, rosemary, garlic powder, salt, pepper, and another drizzle of olive oil over the top.
Bake for 20-25 minutes or until potatoes are tender. Stir to combine well and pour onto a platter or bowl to serve.
For the bacon, you can use pre-cooked real bacon crumbles or freshly cooked bacon.