How to Make It
In a blender, puree the Scotch bonnets with the scallions, thyme, garlic powder, brown sugar, soy sauce, dark rum and water. Season with 1 tablespoon of kosher salt and 1/2 teaspoon of pepper.
Using kitchen scissors, cut out the backbone of each hen. Press down on the breasts to flatten the hens. Set them in a baking dish and coat them all over with the jerk paste. Cover and refrigerate overnight.
Preheat the oven to 300°. Set the hens on 2 large rimmed baking sheets and bake for 45 minutes, until firm but not browned or cooked through.
Meanwhile, light a grill. Grill the hens over moderately high heat, turning occasionally, until cooked through and lightly charred in spots, about 20 minutes. Transfer the hens to a platter and let rest for 10 minutes before serving.