Desalt the cod 24 hours if it is whole. Place in cold water, bring to a boil, remove from heat and leave to poach for 10 minutes. Remove any skin or parts from the cod and flake. Cook the beans in 4 quarts of cold water. Bring to a boil slowly. At the first boiling, change the water for fresh boiling water. Add the carrots, 2 onions and the bouquet garni. Cook everything very slowly. Take out a large cup of beans and pass them through a blender to make a purÄe. In the butter cook the sliced garlic and the chopped onion without browning. Add a large cup of the bean water, add the cream, the tomato paste and the bean purÄe little by little to make a consistant but light sauce. Salt, pepper and nutmeg. Mix in the cod and the beans in an ovenproof casserole, pour on the sauce which should cover everything. Put on the sliced tomatoes, sprinkle on the GruyÅre and heat in the oven at 350F to cook slowly. This dish is delicious reheated.
