Sirloin Burgers With Mushrooms, Swiss, And Balsamic Mayo - cooking recipe

Ingredients

extra virgin olive oil
3 tablespoons finely chopped yellow onions
1 1/3 lbs ground sirloin
1 tablespoon Worcestershire sauce
McCormick's Montreal Brand steak seasoning
4 crusty rolls, split
12 baby portabella mushrooms, thinly sliced
coarse salt
fresh ground black pepper
4 slices swiss cheese
3 tablespoons balsamic vinegar
1/2 cup mayonnaise
4 leaves romaine lettuce

Preparation

Preheat grill pan or large nonstick skillet (for the burgers) over med-high heat.
In a small nonstick skillet over medium heat, saute chopped onion in a drizzle of olive oil for 2-3 minutes; set pan aside.
In a bowl, combine meat, Worcestershire sauce, and steak seasoning; mix in sauteed onion and form into 4 large patties.
Drizzle patties with a touch of oil.
Quick toast your split rolls on the hot grill pan and set aside.
Then add burgers to hot pan; grill 4-5 minutes on each side for medium to medium-well burgers.
Return small nonstick skillet to stove over med-high heat; add 1 tablespoon olive oil and sliced mushrooms; season with salt and pepper, then saute until just tender, 3-5 minutes; remove from heat.
Pile mushrooms on top of burgers just before you are ready to take them off the grill.
Fold each slice of swiss cheese in half and rest on top of mushrooms; place a loose tin foil tent over burgers and turn off heat; let cheese melt down over the mushrooms for 2-3 minutes.
In a small dish, combine balsamic vinegar, mayo, and lots of coarsely ground black pepper.
To assemble burgers: place burgers topped with mushrooms and cheese on bun bottom; slather tops of buns with mayo mixture and add romaine.
Set burger tops in place and serve.