Roast Beef Sandwiches with Sweet-and-Sour Red Onions and Blue Cheese

• 2 cups thinly sliced red onions
• 2 tablespoons red wine vinegar
• 1 teaspoon sugar
• 4 large soft whole grain rolls, toasted
• 1/2 cup crumbled blue cheese
• 12 tomato slices
• 8 ounces thinly sliced roast beef
• 2 cups (packed) small watercress sprigs

1. Combine onions, vinegar, and sugar in medium bowl; sprinkle with salt and pepper.
2. Let stand until onions are soft, tossing occasionally, at least 1 hour and up to 4 hours.
3. Place bottom halves of rolls on work surface.
4. Sprinkle with cheese.
5. Top each with 3 tomato slices, then 1/4 of roast beef.
6. Top each with 1/2 cup watercress, then 1/4 of pickled onions.
7. Cover with tops of rolls.
8. Cut each sandwich in half.

red onions, red wine vinegar, sugar, grain rolls, blue cheese, tomato, beef, watercress sprigs

Taken from www.epicurious.com/recipes/food/views/roast-beef-sandwiches-with-sweet-and-sour-red-onions-and-blue-cheese-106962 (may not work)