Follow these simple steps to make the Ultimate Homemade Big Mac Sliders:

1. Preheat Oven: Preheat your oven to 350°F (175°C) and grease a baking dish.
2. Prep the Special Sauce: In a small bowl, mix together the mayonnaise, ketchup, yellow mustard, white vinegar, garlic powder, onion powder, salt, and pepper. Set aside.
3. Form Patties: Divide the ground beef into 12 equal portions and shape them into small, thin patties that will fit the slider buns.
4. Season the Patties: Sprinkle each side of the patties with salt and pepper to taste.
5. Cook the Patties: Heat a skillet over medium-high heat. Cook the patties for 3-4 minutes on each side, or until they reach your desired level of doneness.
6. Add Cheese: Place a slice of cheddar cheese on each patty just before they finish cooking to melt.
7. Toast the Buns: Cut the slider buns in half and lightly toast them in the oven for about 5 minutes until they are golden brown.
8. Assemble the Sliders: Spread a generous amount of the special sauce on the bottom half of each bun. Top with a patty, then add shredded lettuce, diced onions, and chopped pickles. Cap it off with the top half of the bun.
9. Final Bake: Place the assembled sliders back in the oven for another 5-10 minutes to warm through.
10. Serve Warm: Remove from the oven, serve immediately, and enjoy your homemade sliders!