For the bechamel: Saute the onions and garlic in the olive oil until translucent, and then add the cream and chicken stock. Melt the butter in a separate pan, and then add the flour and whisk. Add the flour mixture to the chicken stock mixture and simmer for 10 minutes. Stir in the lemon juice, sugar, hot sauce and salt. Add the Parmesan and sour cream and stir. Divide the sauce in half, keeping warm. One-half will be used with the macaroni, the other half reserved for plating.
For the onions: Preheat a grill to high heat. Mix together the hot sauce, garlic pepper, salt and onions. Grill until tender and translucent.
For the macaroni: Stir the mustard, paprika, cayenne, white pepper and salt into half of the bechamel. Bring to a boil, and then remove from the heat. Stir in the mixed cheeses and mozzarella until smooth, and then stir in the scallions and tomatoes.
Add the sauce to the cooked pasta and mix. Transfer to a 9- by 13-inch baking dish and let cool completely.
For the burgers: Form the beef into 4 equal patties and sprinkle them with the blackening seasoning. Grill the burgers to your preferred doneness.
For frying the macaroni and assembly: Meanwhile, fill a pot halfway with oil, and heat to 350 to 375 degrees F. Scoop large balls of macaroni using a scoop or melon-baller. Coat in the flour, then dip in the egg wash, and then finally the panko. Deep-fry the balls until the coating is firm.
Toast the hamburger buns and distribute the bacon, dill pickle chips and spicy grilled onions evenly between them, on the bottom half of each bun. Next, place a patty, followed by a macaroni ball on each. Finish with a ladle of the reserved bechamel sauce on top, before putting the top half of the bun on and squishing it down slightly.
NotesThis recipe was provided by a chef, restaurant or culinary professional and may have been scaled down from a bulk recipe. The Food Network Kitchens have not it for home use and therefore cannot make any representation as to the results.