Preheat oven to 400 ºF. Toss sweet potatoes with olive oil and sea salt. Place in roasting pan and bake for 20 minutes. In a large pot, sauté bacon over medium heat. Add onions once the bacon has begun to render fat. Cook until bacon begins to become crisp and onions appear translucent. Add apples and cook for additional two minutes. Add roasted sweet potatoes to the mixture and cook for approximately five minutes or until potatoes begin to become soft. Toss with maple syrup and serve.