This first recipe is so old, they were selling 7-Up in 7 oz. bottles. It sounds like a lot of sugar, but it's also a lot of potatoes, but feel free to adjust.

Seven-Up Baked Sweet Potatoes

6 yams or sweet potatoes
1 cup brown sugar
1 7 oz. bottle 7-Up
1/2 tsp salt
2 tbsp butter
Sprinkle of cinnamon

Cook potatoes either by boiling or baking. I bake mine in the microwave (cut the ends off first). Peel while warm and cut in half. Combine the sugar, 7-Up, salt, and butter in a heavy skillet. Boil 5 minutes, then place the sweet potatoes in the pan in one layer. Sprinkle lightly with cinnamon. Bake in a hot oven for 20 minutes, basting 3 times during baking.

Sweet Potato Balls

2 medium sweet potatoes
1 tbsp melted butter
1/4 cup granulated sugar
1/4 cup brown sugar
1 tsp vanilla
Salt and pepper
12 large marshmallows
1 cup chopped nuts (black walnuts are very good)

Cook the potatoes until tender. Peel and mash well with a fork. Add the butter, sugars, vanilla, salt, and pepper. Coat each marshmallow in a good coating of potatoes and roll in nuts. Place on a greased baking dish and bake at 350 degrees just long enough to heat through so the marshmallows melt slightly. Don't cook too long or they will disappear.

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The way I make sweet potatoes is to bake them either in the oven or microwave until tender, peel and slice about 1/2 inch thick. I put them in a casserole with dabs of butter and pour Amaretto liqueur (or real maple syrup) over and heat them. They can be prepared and then frozen. Thaw in the refrigerator and then warm up in the oven.

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This next one is from The Spice Cookbook, copyright 1964.

Ham Pie with Sweet Potato Crust

Sweet Potato Pastry:

1 cup flour
1 tsp baking powder
1/2 tsp salt
3/4 cup cold, mashed sweet potatoes
1/3 cup shortening, melted
1 large egg, well beaten

Sift the dry ingredients together into a mixing bowl. Add remaining ingredients and stir until well-blended. Chill 1 hour or until dough is stiff enough to handle. Roll or pat to a 1/4 inch thickness to fit the top of a 10 by 6 inch casserole or 9 inch pie plate.

Ham Filling:

1/2 tsp dry mustard
2 tsp water
1/4 cup butter
1/4 cup flour
1 cup milk
1 cup ham stock (or chicken stock)
1 cup diced celery
2 cups diced cooked ham
1 tbsp instant minced onion (or fresh)
1/4 tsp pepper
1/4 tsp garlic powder
1/2 cup cooked peas

Mix mustard with water and set aside 10 minutes. Melt the butter in a saucepan and blend in the flour, stirring and cooking until bubbly. Remove from the heat and add the milk, stock, and celery. Cook 3 to 4 minutes or until the sauce has thickened, stirring frequently. Stir in the mustard and the next 5 ingredients. Turn into a 10 by 6 by 2 inch baking dish, and cover with the sweet potato pastry rolled 1/4 inch thick. Trim it and anchor it to the edge of the casserole. Make 2 slits in the crust to allow steam to escape. Bake in a preheated 400 degree oven for 25 minutes until the pastry is browned.

To make ham stock: simmer a ham bone in water for 1 1/2 hours.