Combine all the sauce ingredients and mix well.

Let stand for at least 20 minutes.

Begin by adding about 1 tablespoon of warm water to the dehydrated minced onion.

Turn your oven or toaster oven to the broiler function.

Cut the slider buns in half if they are not pre-sliced. Place the buns cut side up on a baking sheet. Brush the buns lightly with the melted butter and put them under the broiler until they just begin to toast. Remove the buns from the oven and set aside.

Form the ground chuck into 12 equally sized patties and season both sides liberally with salt and ground black pepper.

Place a stainless-steel or cast-iron skillet over medium-high heat. Cook the patties in the skillet for 2 to 3 minutes on the first side, flip, and cook for 1 to 2 minutes on the other side.

To assemble the burgers, place the bottom buns on a serving platter. Spread a bit of the Big Mac sauce on each bottom bun, along with a small spoonful of minced onions. Add a burger patty to each bun and top the patty with cheese, two pickle slices, and shredded lettuce. Spread some Big Mac sauce on the top buns and place them down over the burgers. Brush some additional melted butter over the top buns and sprinkle with sesame seeds. Serve immediately.