• Preheat a grill pan over medium-high heat.
• Combine the beef, salt, allspice, cayenne, garlic powder, onion powder, oregano, pepper flakes, brown sugar, thyme and black pepper in a large bowl and gently mix until just combined.
• Form the meat into eight 2-ounce patties, then press the center of each with your thumb to create an indent. Coat the grill pan with cooking spray.
• Grill the sliders indent-side up until the internal temperature registers 150 degrees F, 2 to 3 minutes per side, placing a slice of cheese on each patty once you flip them. Cover the patties on the grill pan with a metal bowl to allow the cheese to melt. (The cheese will melt over the sides of the patties.) Remove the patties to a plate and cover loosely with foil to rest.
• Meanwhile, brush the buns with the melted butter and grill until lightly toasted, about 2 minutes per side.
• Assemble the sliders by putting a tablespoon-sized dollop of the Ketchup on the bun tops and bottoms, then top each bottom with a patty. Finish with one Onion Ring on top of each slider. Close sliders and serve immediately.

Jerk Ketchup:

• Yield: 1 1/4 cups
• Combine the ketchup, lime juice, allspice, cayenne, garlic powder, onion powder, oregano, pepper flakes, brown sugar, thyme and salt in a medium nonreactive bowl and mix until incorporated.

Red Ale Onion Rings:

• Pour 4 inches oil into an 8-quart Dutch oven and bring to 350 degrees F over medium-high heat.
• Meanwhile, peel the onions and slice into 1/2-inch-thick rings.
• Combine the flour, salt, garlic powder and black pepper in a large bowl. Whisk in the ale until the ingredients are combined. The batter should be thick but slightly loose.
• Place a wire rack in a sheet pan. Working in batches, dip the onion rings into the batter. Drain any excess batter back into the bowl, then slowly lower the onions into the hot oil. Cook, flipping the onions every 30 seconds, until golden brown, 2 to 3 minutes. Transfer the onions to a wire rack with a spider and lightly season with sea salt.