Soak beans overnight in cold water. Drain in the morning.

Put in a large heavy pot and add 4 cups of cold water, cover and heat to boiling simmer 30 minutes (an important step as beans will never get more tender without this step, no matter how long you cook them). Drain.

Place onion slices and turkey leg in the bottom of a large heavy casserole dish or bean pot. Mix seasonings and turn into pot. Add beans and water to cover.

Cover and bake at 250 degree oven for 7 hours. When the beans are tender, remove 1 cup of beans and mash, then stir back into pot. Cover and tonne to bake. Add water as needed to keep beans just covered. One hour before serving remove cover and darken beans.