Caramelised onion and blue cheese sweet potatoes

Ingredients (4 servings): 2 large orange sweet potatoes (see Notes) ¼ cup olive oil 3 medium brown onions, thinly sliced 2 tablespoons brown sugar 1 tablespoon balsamic vinegar 1 tablespoon fresh rosemary, finely chopped 75g blue cheese 1 teaspoon fresh thyme, finely chopped   Method: Preheat oven to 200C/180C fan-forced. Place sweet potatoes on a…