Broiled Tomato and Cheese Sandwiches
- Preheat broiler with cooking rack 6 inches from heat. Place bread on a baking sheet and broil until lightly toasted (not yet browning), about 30 seconds; turn and broil another 30 seconds.
- Brush tomato slices with olive oil and place on a second baking sheet. Broil 2 minutes, turn over, and broil 3 minutes more, until lightly browned.
- Meanwhile, top each bread slice with cheese and onion slices. When tomatoes are done, remove from oven. Place cheese-topped bread slices under broiler for 1 minute, until cheese melts.
- Remove bread slices from oven spread with mayonnaise if desired. Top with arugula(or greens of choice), basil leaves, and broiled tomato slices. Sprinkle with salt, pepper, and sliced avocado, if using. Garnish with chopped basil and serve immediately.