Heat oil in skillet.Saute onions and garlic 5 mins.Add the tomatoes, salt and pepper and cook over low heat 5 mins. Cool 10 mins. Flake the crab meat, stir in the onion mixture, coconut, and egg yolk. Shape into 12 patties for a meal or into smaller cakes or balls for hor d ' oeurves.Saute in butter until lightly browned on both sides.