Add the onion, tomato, garlic, bell pepper, Scotch bonnet pepper, and scallion, and cook until the ingredients are soft, about 3 minutes
Add the ackee, thyme, chili powder, salt, and pepper, gently folding the ingredients together
Cook for 5 to 8 minutes or until the mixture is heated through; remove from heat
Serve assembly-line style, with the ackee mixture, guacamole, grated cheese, shredded lettuce or cabbage, cilantro, salsa, and sour cream (if using) in colorful bowls next to a basket of soft or hard taco shells
Alternately, serve a large platter of already assembled tacos: fill each shell with a few tablespoons of ackee, layer with lettuce, guacamole, and cheese, and top with a mound of fresh cilantro for a mouthful of exotic flavor