In a large, nonreactive bowl, combine the curry powder, garlic, Scotch bonnet pepper, shallots, green onions, and vinegar. Add the goat meat and toss to coat each piece with the seasoning. Cover and refrigerate to marinate for 8 to 12 hours.
Heat the butter and oil in a large Dutch oven over medium-high heat. Add the goat stew meat in batches, and cook until well-browned, about 5 to 8 minutes per batch. Remove each batch of browned goat meat and set aside until it has all been browned. Return all of the meat to the pan and add the tomatoes, salt, and pepper. Add 1 quart of water, or enough to cover the meat, and bring to a boil. Reduce heat to a simmer, cover, and cook until tender, about 2 hours, skimming the grease off the top of the stew occasionally.
Combine the remaining 3 tablespoons of water and the cornstarch in a small bowl, whisking until smooth. Whisk the slurry into the stew and bring to a boil. Allow stew to gently boil for 5 minutes, stirring occasionally, until slightly thickened. Remove from the heat.
To serve, place steamed rice on 1 piece of Roti Bread. Spoon the goat stew over the rice and fold the ends of the roti over to enclose the stew. Serve immediately with Fried Plantains.
Yield: about 2 1/2 quarts