Sirloin Burgers with Balsamic Mayo, Mushrooms and Swiss

Name: Sirloin Burgers with Balsamic Mayo, Mushrooms and Swiss
Cuisine: American
Ingredients: 1/4 cup chopped onion; 1 1/3 pounds ground sirloin, 90 percent lean; 1 tablespoon Worcestershire sauce (eyeball the amount); Steak seasoning blend or coarse salt and pepper (preferred brand: McCormick Montréal Steak Seasoning); Extra-virgin olive oil, for drizzling plus 1 tablespoon (1 turn of the pan in a slow stream); 4 crusty rolls, split; 4 portobello mushrooms, thinly sliced; Coarse salt and pepper; 4 slices Swiss cheese; 3 tablespoons aged balsamic vinegar (eyeball the amount); 1/2 cup mayonnaise or reduced fat mayonnaise; Coarse cracked black pepper; 1/4 pound baby spinach; 2 vine ripe tomatoes, sliced; 2 scallions, chopped; 4 romaine leaves, optional

8 steps

Juicy sirloin burgers seasoned with Worcestershire and steak spices, topped with sautéed portobellos and Swiss, then finished with balsamic black-pepper mayo.

Updated at: Thu, 15 Oct 2026 21:41:11 GMT

Nutrition balance score

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Ingredients

4 servings

¼ cuponion

chopped

1.33 poundsground sirloin

90 percent lean

1 tablespoonWorcestershire sauce

eyeball the amount

Steak seasoning blend

or coarse salt and pepper, preferred brand: Montréal Steak Seasoning

Extra-virgin olive oil

for drizzling plus 1 tablespoon, 1 turn of the pan in a slow stream

4crusty rolls

split

4portobello mushrooms

3 tablespoonsaged balsamic vinegar

eyeball the amount

½ cupmayonnaise

or reduced fat mayonnaise

Coarse cracked black pepper

0.25 poundbaby spinach

Instructions

Step 1

Preheat grill pan or large nonstick skillet.

Step 2

Sauté onions in a small pan over moderate heat for 3 to 5 minutes until tender.

Step 3

Combine meat with Worcestershire sauce, sautéed onion and steak seasoning blend or salt and pepper. Form 4 large patties. Drizzle patties with a touch of extra-virgin olive oil.

Step 4

Quick toast your split rolls, then add burgers to grill pan or skillet. Grill or pan-fry burgers 4 to 5 minutes on each side for medium well doneness.

Step 5

Heat a small to medium nonstick skillet over medium-high heat. Add a little oil and mushrooms. Season mushrooms with a little salt and pepper and sauté until just tender, about 3 to 5 minutes. Remove from heat.

Step 6

Pile mushrooms on top of burgers just before you are ready to take them off the grill or out of the pan. Fold each Swiss cheese slice in half and rest on top of mushrooms. Place a loose tin foil tent over the burgers and turn heat off under pan or grill. Allow the cheese to begin to melt down over mushroom and burgers, about 2 to 3 minutes.

Step 7

Combine balsamic, mayonnaise and coarse cracked black pepper in a small dish.

Step 8

To assemble, place burgers with mushrooms and Swiss cheese on bun bottom. Slather tops of buns with balsamic black pepper mayonnaise and baby spinach. Set burger tops in place and serve with sliced vine ripe tomatoes, drizzled with oil, seasoned with salt and pepper and garnished with scallions.