Prepare a steamer.
Large Portobello Mushrooms (8)
caps until mushrooms are tender, about 7 minutes.
Place cooked mushrooms in a food processor with minced
Garlic (4 cloves)
Steak Sauce (3 Tbsp)
Breadcrumbs (3/4 cup)
Freshly Ground Black Pepper (1/2 tsp)
Pulse just until mixture comes together, about 20 pulses or 30 seconds.
Divide mixture into six to eight 6 oz. patties, 4" wide by ⅓ " thick. Place on a plate and refrigerate for 20 minutes or until ready to use.
Thinly slice the
Red Onion (1)
Butter (3 Tbsp)
in a 12" skillet over medium-high heat. Sauté onions until soft, about 8 minutes.
Balsamic Vinegar (2 Tbsp)
Dried Thyme (1/2 Tbsp)
Salt and Pepper (to taste)
. and cook until onions are slightly caramelized, about 7 minutes more. Remove from the pan and reserve.
Wipe out skillet and heat
Olive Oil (2 Tbsp)
over medium-high. Cook portobello burgers, until toasted on each side and cooked through, about 12 minutes (6 minutes per side).
Top each burger with
Blue Cheese (3/4 cup)
and continue to cook until just melted, about 2 minutes.
Sesame Hamburger Buns (4)
and top with burgers.
Top with onions, and serve with
Pickles (to taste)