Caramelized Onion–and–Blue Cheese Mini Burgers

Ingredients

• 1.5 cups arugula 
• 0.5 teaspoon pepper black freshly ground
• 1.5 tablespoons cheese blue crumbled
• 1 pound ground sirloin 
• 2 tablespoons canola mayonnaise 
• 1 medium onion thinly sliced
• 0.5 teaspoon salt 
• 8  slider buns toasted
• 8 slices tomatoes thin

Equipment

• food processor
• bowl
• frying pan
• grill
• kitchen thermometer
• grill pan

Directions

1. Heat a medium nonstick skillet over medium-high heat.
2. Add onion to pan; coat onion with cooking spray. Cook 15 minutes, stirring frequently, until tender and browned.
3. Remove pan from heat. Finely chop 1/4 cup onion, and place in a medium bowl, reserving remaining onion in pan.
4. Add salt, pepper, and beef to caramelized onion in bowl; mix well. Divide beef mixture into 8 equal portions, shaping each into a 1/4-inch thick patty.
5. Heat a grill pan over medium-high heat.
6. Place patties on grill pan. Grill 3 minutes on each side, until a thermometer registers 160 or until desired degree of doneness.
7. Place mayonnaise and blue cheese in a food processor; process until smooth.
8. Spread blue cheese mixture evenly on bottom halves of buns.
9. Place 1 patty on bottom half of each bun. Top patties evenly with arugula, tomato slices, and remaining caramelized onion; cover with bun tops.