Home-made Burger with "Shake Shack" Sauce

I thought it would be a good time to break out the meat grinder that has been rarely used since being bought. I could think of no better way to use it then to make freshly ground burger with the 2 or 3 pounds of "flap steak"( a cheap cut of meat, similar to hanger or skirt steak) I had in the fridge. I've also been meaning to try the secret "Shack Sauce" from the restaurant Shake Shack in the NYC and at Citi Field. It had been decoded by the guys over at Serious Eats a few weeks ago, which can be seen here.

Home-made Burgers(makes 4 burgers)

1-2 pounds flap meat, any kind of beef can be used

4 burger rolls, preferably Martin's Potatoes Rolls

Shack Sauce, recipe follows

4 slices cheese, if desired

"Shack Sauce"(makes about 3/4 cup)

1/2 cup mayonnaise

1 tablespoon ketchup

1 tablespoon yellow mustard

1/2 kosher pickle

1/4 teaspoon garlic powder

1/4 teaspoon paprika

pinch cayenne pepper

Directions

1. Cut Flap steak into 1 inch cubes and lightly season with salt.
   
   
2. Put into meat grinder with the fine grind attached.
   
   
3. Form ground meat into 5 oz. patties and season one side with salt and pepper.
4. To make sauce, combine all ingredients in food processor and blend until smooth.
5. Heat a pan over medium heat and put seasoned down and then season the other side.
6. Cook 2-3 minutes on each side, place cheese on after flipping if desired.
7. Place burger on bun, apply sauce and enjoy!