Roast Beef and Carmelized Onion Sliders

Why I Love This Recipe
Ingredients You'll Need
1/3 cup Horseradish Mayonnaise
8 (3-inch) slider buns, sliced in half horizontally and toasted
Kosher salt
Freshly ground black pepper
8 ounces thinly sliced roast beef
1 cup caramelized onions
10 cornichons, thinly sliced lengthwise
2 cups watercress (about 2 ounces), washed and dried
Directions
Divide the horseradish mayonnaise among the tops and bottoms of the buns
Season with salt and pepper (optional)
Divide the roast beef among the 8 bottom buns
Top each slider with caramelized onions, cornichons, and watercress and close with a top bun
Recipe Tips:
*For Carmelized Onion tips go to: http://www.bonappetit.com/test-kitchen/common-mistakes/article/caramelized-onions-common-mistakes
*Don't cut too thin - Use a combination of oil and butter - Don't crank the heat (will take about 30-45 minutes, but worth it - They should be a rich brown in color and soft, but not mush