Melt the sliced onions in the mixture of butter and olive oil. Add the peppers, the ginger and the thyme, pour very slowly one cup of boiling water, the tomatoes and the octopus, pre-cooked and cut in pieces, cover and simmer for 1 hour. Drop the olives in boiling water. After 5 minutes drain and stone. This can be done easily if the olives have been incised spirally before boiling. Add the olives the last moment, stir for a few minutes, remove from stove and sprinkle with the lemon juice and Madeira wine.