I found this on the Food Timeline and I have some sweet potatoes already cooked, measured and ready to use in the freezer. It’s going to be a snow day experiment.
 “Sweet Potato Pudding.
- 1 lb parboiled sweet potatoes.
- 1/2 cup of butter.
- 3/4 cup cup of white sugar.
- 1 tablespoonful of cinnamon.
- 4 eggs, whites and yolks beaten separately.
- 1 teaspoonful of nutmeg.
- 1 lemon, juice and grated rind.
- 1 glass brandy.
Let the potatoes get entirely cold, and grate them. Cream the butter and sugar; add the yolks, spice and lemon. Beat the potato in by degrees, to a light paste; then the brandy, lastly the whites. Bake in a buttered dish, and eat cold.” —The Dinner Year-Book, Marion Harland [Charles Scribner’s Sons:New York] 1878 (p. 164)
I used 2 c. baked sweet potatoes ( a pint’s a pound the world around and 2 cups in a pint, right?), the juice and zest of half of a cava cava orange (no lemons in the house, today) and a shot glass of cognac (Remy Martin VSOP, if you want to be specific). Beat the egg whites to soft peaks and folded them in before baking in a souffle dish for @ 1 hour at 350º F.