Peel and finely grate the 2 smoked garlic cloves.

Combine the grated smoked garlic, black pepper, salt, pink peppercorns, smoked paprika, white vinegar, mustard, ketchup, and harissa in the mixing bowl.

Coat the 2 boneless chicken thighs thoroughly with the marinade.

Cover and refrigerate the marinated chicken thighs for 15 minutes.

Peel the 2 ripe plantains and cut them lengthwise into thin slices.

Thinly slice the onion.

Heat 1 tablespoon vegetable oil in the frying pan over medium heat.

Cook the sliced onion with the cane sugar for 8 minutes until soft and caramelized.

Transfer the caramelized onion to the mixing bowl.

Stir the crème fraîche into the caramelized onion until a creamy sauce forms.

Heat the remaining 1 tablespoon vegetable oil in the frying pan over medium-high heat.

Fry the plantain slices for 3 minutes per side until golden and tender.

Remove the fried plantains from the pan and set them aside.

Cook the marinated chicken thighs in the frying pan for 6 to 8 minutes per side until the center reaches 165°F (74°C).

Place the smoked cheddar over the cooked chicken thighs and let it melt for 1 minute.

Warm the 2 burger buns cut-side down in the frying pan for 1 minute.

Spread half of the creamy caramelized onion sauce over the bottom halves of the burger buns.

Place one fried plantain layer and one cheese-topped chicken thigh on each bun.

Close each burger with its top bun and serve immediately.