Combine the patty ingredients and portion into 18 balls. Press them down slightly between your palms to be slightly bigger in diameter than your buns. Place a cooking rack on a parchment paper covered baking sheet. Line out patties and place in oven. Bake for 15 minutes.
In a small bowl, combine mayo and relish.
Remove patties from oven and top each with a quarter slice of cheese. Return to oven for 5 minutes more. Remove from oven.
Build the slider - Smear bottom bun with relish mayo. Add shredded lettuce and onion slices, then add patty. Next a pickle chip and the top bun. Secure with long toothpick or wrap in food paper.