apFoodbeasta dreamt up this mashup masterpiece, and it's something we've been drooling over since it first told us about it. But alas - when we tried to order this for ourselves, we were met with rejection and despair. While you can simply order a Double-Double with Animal Style fries and DIYa it yourself at In-N-Out, we thought we'd take the opportunity to show you how to not only make the Monkey Style burger at home but also teach you the tricks of the trade to getting those irresistible mustard-grilled patties that are synonymous with the Double Double. Not a meat eater? Take a look at our Animal Style grilled cheese recipea.br br ia Monkey Style In-N-Out Burger From Nicole Iizuka, POPSUGAR Foodp IngredientsolbFor the secret spreadb:libr 1 cup mayonnaiselibr 12 cup ketchuplibr 2 tablespoons dill pickles, finely choppedlibr 1 teaspoon yellow mustardlibr 12 teaspoon saltlibr 12 teaspoon ground pepperlibr 12 teaspoon sugarlibr 1 teaspoon apple cider vinegarliolbr olbFor the burgerb:libr 1 large yellow onion, finely dicedlibr 2 teaspoons vegetable oillibr 14 cup french frieslibr 6 ounces ground beef, 85 leanlibr Pinch saltlibr Pinch pepperlibr 2 teaspoons yellow mustardlibr 2 slices American cheeselibr 1 potato bun, sliced in halflibr 1 teaspoon butterlibr 2 tablespoons secret spreadlibr 4 dill pickleslibr 2 slices tomatoes, 14-inch thicklibr 2 iceberg lettuce leavesliolbr Directionsolbr liTo make the secret spread: Mix together mayonnaise, ketchup, pickles, mustard, salt, pepper, sugar, and apple cider vinegar.libr liTo make caramelized onions: Add diced onions and oil to a sauté pan set over medium-high heat. Cook, stirring occasionally, until deeply caramelized. Deglaze pan with 12 teaspoon water. Set aside.libr liTo make the french fries: Cook french fries according to package directions.libr liTo make the burger: Heat up a cast-iron skillet until it just starts to smoke. Form ground beef into 2 patties, approximately 4 inches across. Season with salt and pepper. Place patties onto cast iron and cook for 1-2 minutes. While cooking, spread mustard onto the uncooked side of the burger. When ready, flip the patties and top with a slice of American cheese. Cook until burger is cooked through.libr liTo assemble: Toast bun on a hot skillet with butter, until the edges are golden brown. Starting with the bottom bun, spread 1 tablespoon of spread on the bottom, and top with pickles, tomatoes, and lettuce. Add 1 burger patty, a heaping tablespoon of caramelized onions, and the second patty. Top that with french fries, more spread, and another scoop of onions. Finish with the top of the bun.