Best Duck Fat Seared Beef Burger with Garlic Fennel Confit and Homemade mayonaise
1 large fatty duck breast (fat for rendering and 7oz. meat, quartered, for burgers)
1 & 1/3 cup very thinly sliced fennel bulb, 2 tablespoons chopped frond for mayo
2 & 3/4 teaspoons kosher salt, divided
1 & 1/8 teaspoon fresh ground black pepper
28 medium cloves peeled garlic, root end trimmed
1 cup light olive oil
1/3 cup, plus 1 tablespoon fig preserves
2 tablespoons, plus 1/2 teaspoon Dijon mustard, divided
1 & 1/3 cup soft fresh potato or white bread, torn into bits
6 tablespoons whole milk
1 large fresh egg yolk, plus one extra yolk if needed, pasteurized recommended for safety
1 tablespoon sherry vinegar
30oz. fresh skirt steak, cut in 6 pieces
5 juniper berries, ground
8oz. cow’s milk Blue cheese such as Sweetgrass Dairy Asher Blue, in 6 slices/portions
6 rich buttery type bakery Buns, sesame seeded if possible, split
2 cups of young Arugula leaves
Remove duck fat from breast, score fat with sharp knife and place in large iron skillet over medium
heat on grill. Cook, turning occasionally, until you have about 8 tablespoons rendered fat, about 20 minutes. Leaving 1 tablespoon fat in pan, sauté fennel bulb with 1/4 teaspoon salt, and 1/8 teaspoon black pepper, over medium flame for 6-8 minutes until beginning to caramelize. Remove from heat, stir in garlic. Cool slightly, spoon into a small heatproof saucepan with olive oil, (don’t clean skillet). Cook over very low heat for 40 minutes or until garlic is very soft. Small bubbles will rise, but do not “boil” the oil. Cool confit until oil is room temperature. Strain out garlic and fennel, saving 3/4 cup of the oil for mayonnaise. (save remaining oil to supplement duck fat if necessary to make 1/2 cup) In a small bowl, mash confit into a chunky “confiture” and set aside.
Meanwhile for sauce, in small bowl, mix preserves with 2 tablespoons mustard, set aside. In small bowl, moisten bread with milk and set aside. For mayonnaise, in food processor or blender, whisk one yolk, 1/4 teaspoon salt, and 1/2 teaspoon mustard. Add add 3 tablespoons cooled olive oil drop by drop, then add vinegar, add remaining oil in a very thin stream. If the mayonnaise “breaks”, pour broken mayonnaise into a small bowl, add remaining egg yolk to clean processor bowl, whisk in broken mayonnaise, drop by drop until all combined, stir in fennel frond. Cover and chill.
For burgers, in clean processor bowl, pulse duck breast meat until coarsely ground, remove to large bowl. Do the same with the beef in 2 portions. Pick any large strings of tough fat from beef. Add all beef and duck back to processor with 5 tablespoons of rendered duck fat, pulse until just combined and meat is more finely ground. Return to bowl and with fork, gently stir in soaked bread, juniper, remaining 2 &1/4 teaspoons salt and teaspoon pepper. Form into 6 equal patties to fit buns, with a dimple pressed into center of each for more even cooking.
Return the large skillet to grate over high heat until very hot. Add a tablespoon of duck fat, Sear 3 burgers at the time quickly on each side, then transfer to grill grate to finish. Add last tablespoon of the duck fat for second batch of patties. Grill until medium, or desired doneness, 3-4 minutes per side, basting with fig sauce. Remove, add cheese, cover loosely to keep warm.
Toast buns over medium heat until golden. Spread tops with confiture, and bottoms with 2 tablespoons mayo (save any extra mayonnaise), topped with lettuce, then burgers and top bun. Makes 6