Heat skillet over medium heat. Toast peppercorns & allspice berries until aromatic, about 3 minutes. Remove and smash or grind.
Coat pan with oil. Add chicken and brown chicken on all sides, 2-3 minutes adding pepper and allspice. Set aside & cover.
Over medium-high heat, add onion,garlic, ginger root, habanero peppers, sweet potato and red pepper. Sauté until browned, about 4 minutes.
Pour in broth, bring to a boil over high heat. Add orange zest/peel and dark rum. Add (optional) habanero powder for additional "heat." Reduce burner to medium and cover to cook veggies until tender, about 10 minutes, stirring half way through. Meanwhile, make a slurry with cornstarch and orange juice.
Uncover, stir and squeeze in lime juice. Add chicken. Slowly add orange juice slurry and cook until sauce is thick, adding chicken broth to thin it out if needed. Cook another 5 minutes to finish chicken and incorporate flavors.
Garnish with coconut and scallions.
This recipe can be made using leftover chicken, ground pepper & allspice, jarred garlic & ginger for a quicker meal, although flavor won't be as distinctive.
Another quick meal/pantry option is to substitute 1/2 cup of orange/apricot marmalade in place of the orange juice & cornstarch slurry, lime juice and orange peel. The final flavor will be sweeter and more pungent.
For extra zing at the table, Trinidad mustard sauce or a sweet-chili habanero sauce are nice condiments to use.