combine the seasoning mix ingredients in small bowl. Dissolve the flour in 2 tablespoons of the stock. Melt butter in a heavy 5 litre pot over high heat. When it sizzles, add the onions and plantations and cook, stirring constantly, until the onions begin to brown and the plantains are tender, about 8 minutes. Add the remaining stock and deglaze the pot (that's just a fancy professional chef's term for scraping and using the liquid to loosen the brown bits.) Add the seasoning mix, flour-stock mixture, and coconut milk. Stir well, then stir in the heavy cream. Bring just to a boil, stirring constantly, and add the oysters and their liquor. Return to a gently boil, reduce the heat to medium, and cook, stirring occasionally, just untilt he oysters are heated through. about 3 minutes. Remove fromt he heat and serve.