Grilled Sirloin & Caramelized Onion Flatbread Recipe Type: Entree Prep time: 5 mins Cook time: 50 mins Total time: 55 mins Serves: 6 Ingredients Caramelized Onions: 1 tablespoon olive oil 1 medium red onion, sliced 1 large white onion, sliced 1 tsp paprika 1/2 tsp kosher coarse salt 1 tablespoons golden balsamic vinegar Flatbread Assembly: