Preheat the oven to 400°F.
Slice the sweet potato in half. Put the olive oil in the bottom of baking dish and rub it over the cut halves (both cut side and skin). Sprinkle with salt and pepper and put the sweet potatoes cut side down in the dish.
1 purple sweet potato, 2 teaspoons olive oil, salt and pepper
Bake for about 45 minutes until the flesh has started to soften.
Meanwhile, rinse and drain the beans and combine them in a small bowl with the grated Parmesan, garlic, and rosemary.
1 can (15 ounces) white beans (e.g. Great Northern, cannellini), ¼ cup (28 grams or 1 ounce) grated Parrmesan, 1 clove garlic, minced, 1 tablespoon minced fresh rosemary
When the sweet potatoes have softened, flip them over so they are cut side up and top with the bean mixture. Bake for 5 to 10 minutes, until the beans have warmed and the cheese has melted. Serve immediately.