Kosher salt and freshly ground black pepper to taste
4 slices Gruyere cheese (about a scant 1/4 pound)
4 leaves green leaf lettuce, washed and dried
4 slices tomatoes
4 soft potato or brioche rolls
Heat oven to 350 degrees F. Portion beef into four 8 ounce patties. Wrap
tightly and keep refrigerated until ready to use.
Combine grated parmesan cheese with panko. Place mixture on a dry sheet
pan and bake in oven for approximately 10 minutes. The flakes should turn a
rich golden brown. Set aside to cool.
Melt butter with olive oil over medium heat and gently sauté the sliced
onions until they are lightly browned and begin to soften. Add the white wine
(away from the open flame) and cook for 2 to 3 minutes to evaporate the wine.
Add beef broth, bring to a boil, reduce to a simmer and add the thyme sprig.
Continue cooking onions uncovered until the beef broth has nearly evaporated
and the onions are very soft with a rich ebony color. Remove the thyme. Reserve
in a warm place for immediate use, or cool and refrigerate.
Heat a heavy skillet (preferably cast iron) over medium high heat. Season
burgers with salt and pepper. Place burgers in skillet (no oil necessary, but
a small tab of butter adds extra flavor). Cook for approximately 4 to 6 minutes
per side for medium.
Toast buns. Warm onions gently. Place the onions on the burgers and place
a slice of Gruyere cheese on each burger. Allow cheese to melt. Place burgers
on toasted buns, top with the Parmesan crunch flakes, and garnish with lettuce
Source: Doug Vincent, chef, Wayne's Burger Deluxe, Wayne, New Jersey