Soak peas for at least 8 hours or overnight in water to cover; drain. Heat butter in a large, heavy pot and saute onion and leek until tender. Add peas, ham, salt pork (in one piece), garlic, water and salted herbs. Bring quickly to a boil, lower heat, partly cover, and cook gently for 2 to 3 hours or until peas are tender. Stir occasionally during cooking, adding more water if necessary. Remove salt pork, cut in small pieces, then return to soup. May be frozen.
Source: A Taste of Quebec by Julian Armstrong Posted by Linda Davis