Roast Beef Sandwiches

Serves 6

3 large red onions, cut into 6 wedges and peeled

7 tbsp extra virgin olive oil, divided

1/4 cup balsamic vinegar

salt and pepper to taste

1 cup mayonnaise

1/4 cup fresh basil leaves, chopped

1 1/2 tbsp fresh lemon juice

2 1/4 tsp grated lemon peel

6 ciabatta buns, cut in half

1 lb roast beef, thinly sliced

lettuce

Preheat oven to 425. Line large baking sheet with foil.

Gently toss red onions, 5 tbsp oil and vinegar in large bowl. Sprinkle with salt and pepper. Arrange onions in a single layer on prepared baking sheet and bake until browned at edges and just tender (about 40 minutes). Remove and cool to room temperature.

In a small bowl mix mayonnaise, basil, lemon juice, lemon peel and remaining oil (onions and mayonnaise can be made up to 2 days ahead, covered separately and refrigerated).

To assemble, spread mayonnaise on buns, top with beef, onions and lettuce.