For decades, cakes using plain mashed potatoes as a main ingredient were very popular — probably in part because they could make use of leftover potatoes, but also because a mashed potato cake stayed moist longer than traditional all-flour cakes.
The Des Moines Register in Iowa even introduced a recipe with a little old-timey — yet slightly helpful — banter back in 1917:
“They’re going to drive in for several days — Polly, and Ned, and Mildred, and the others. Oh, good gracious, Bettina! What in the world will you do with them all?” Aunt Ruth looked horrified at the ideas.
“Just what I had begone to do when you came — turn tonight’s dinner into a picnic, and make the other meals as informal as possible, too.
“Help me think of what to bake for the picnic,” Bettina said to Aunt Ruth.
“Make one or those delicious mashed potato cakes that you’ve made before. They won’t eat half of it tonight, and it will stay moist and fresh as long as they are here.”
“That’s a good idea, Ruth; I’ll do it.
“I remember the first time I made a mashed potato cake, I was surprised at the way the mashed potatoes affected the batter. It became so thin and watery at once that I thought something was surely wrong. But it thickened up, and when it was done, was like any other cake, though a little more moist, perhaps.
“It really is a very good kind of cake to make, because it seems just as fresh when it is several days old as it does at first.”
Potato caramel cake (1900)
2/3 cup butter 2 cups granulated sugar 2 cups flour 1 cup mashed sweet potatoes (hot) 1/2 cup sweet milk 4 eggs 2 teaspoons baking powder 1 cup grated chocolate or 2 squares melted 1 cup chopped walnuts 1/2 teaspoon cloves 1/2 teaspoon nutmeg 1/2 teaspoon cinnamon
Cream the butter and sugar and yolks of eggs; add milk, potato, spice and chocolate. Sift baking powder into flour and beat whites of eggs stiff. Stir flour into the batter, beat the eggs in and add nuts last. Bake in a long biscuit pan.
Chocolate potato cake recipe (1918)
This cake keeps deliciously moist and fresh for some days after it is made.
Cream one-third of a cupful of margarine and beat in half a cupful of crushed maple sugar. Whip two eggs lightly, add half a cupful of white sugar and combine the two mixtures.
Then mix in half a cupful of creamy, mashed potatoes (hot), one ounce of melted bitter chocolate, one-quarter of a cupful of sweet milk and one cupful of flour sifted with one and three-quarter teaspoonsful of baking powder and half a teaspoonful each of ground cinnamon and mace.
Beat the batter thoroughly, add half a cupful of chopped walnut meats, dusted with a little flour, and bake in a loaf in a moderate oven.
Chocolate spice mashed potato cake (1915)
Cream one cup of butter and two cups of granulated sugar. Add one- half cup of sweet milk or water, the yolks of four eggs, one cup of nuts (floured), one-half cup of cocoa dissolved in hot water, one cup of warm mashed potatoes, one teaspoonful of cinnamon, and one half teaspoonful of cloves mixed with two cups of flour, two teaspoonsful of baking powder, the whites of four eggs folded in lightly, and one teaspoonful of vanilla.
Cocoa mashed potato cake (1928)
Here is a mashed potato cake recipe that’s slightly different from others. It requires:
2 cups flour 2 teaspoons baking powder 2 cups sugar 3 tablespoons of cocoa 1 teaspoon cinnamon 1/2 teaspoon cloves 1/2 teaspoon allspice 2 eggs 1 cup of hot mashed potato 1/2 of a cube of butter (1/4 cup) 1 cup of chopped nuts 1 cup of raisins 3/4 of a cup of milk A pinch of salt
Sift all the dry ingredients together, then add the potatoes and butter. Break in the eggs. Add the milk. Beat well. Lastly, add the nuts and raisins which have been dredged with flour. This may be baked in layers. but makes an excellent loaf cake. Use a cocoa icing.
Mashed potato cake (1929)
Cream 1-1/2 cups sugar with 2/3 cup butter; add 1/2 cup milk, 1 teaspoon vanilla and 2 beaten egg yolks. Beat for 2 minutes. Add 3 squares melted [unswseetened] chocolate, 1 cup warmed mashed potato, 1/4 teaspoon salt, 2-1/4 cups flour, 4 teaspoons baking powder. Beat 3 minutes. Fold in 2 egg whites, beaten stiff.
Bake in layers in a moderate oven [approximately 325-350F] for 25 minutes. Put together with White Mountain frosting between the layers and on top.