Beat the eggs together with the vanilla until it bleaches. Set aside. Melt the chocolate together with the margarine. Add the cocoa, flour, salt and sweeten with Le Zuc. With a wooden palette, add the egg mix slowly. Incorporate the nuts. Empty in a square or rectangular mold covered with wax paper. Bake for 20 min at 390°F. It should be moist in the center. Keep refrigerated.