Ingredients
4
tsp finely chopped rosemary
4
tsp distilled white vinegar
2
pounds thinly sliced roast beef
1
red onion, thinly sliced (optional)
Directions
1.
Place chopped rosemary and vinegar in medium bowl. Let stand 15 minutes. Whisk in mayonnaise and garlic. Season rosemary mayonnaise to taste with salt and pepper. (Can be made 2 days ahead. Cover and keep refrigerated.)
2.
Line large platter with romaine leaves. Arrange roast beef atop lettuce. Sprinkle with onion slices, if desired. Serve roast beef and rosemary mayonnaise separately.