Place beans and garlic in a medium saucepan and cover with cold water. Bring to a simmer and cook until the beans are tender, about 1 to 1 1/2 hours. When the beans are tender, stir in the coconut milk, green onions, Scotch bonnet, and thyme, and increase the heat to a boil. Stir in the rice, add some salt and pepper, cover the pot, and cook until the rice is tender and has absorbed most of the liquid. Transfer to a large serving bowl, taste for seasoning, adding more salt and pepper if needed, and garnish with sliced green onions.