Recipes: Bacon burgers on brioche buns

Preparation:  Preparation time: 20 mins Cooking time: 20 mins Serving: 8 Ingredients: 2 medium red onions (thinly sliced) 6 tablespoons extra-virgin olive oil (plus more for brushing) ½ cup mayonnaise 2 tablespoons fresh lemon juice Salt and freshly ground pepper 8 slices of thick-cut bacon (12 ounces) 3 pounds mixed...