Here’s a recipe typed on a white index card that was found in a large collection of recipes. I did make a correction or two on the typos but otherwise I’ve typed it as-is, you’ll find the recipe details underneath the picture below.

Coffee Sponge Cake

Mix and let cool:

One tablespoon instant coffee
One cup boiling water

In large bowl beat until thick:

6 egg whites
1/2 teasp. Cream of tartar
Add 1/2 cup sugar

Beat in another bowl:

6 egg yolks (until lemon colored)
1 1/2 cups sugar
1 teasp. vanilla

Sift together:

2 cups flour
3 teasp. baking powder
1/2 teasp. salt

Add flour mixture and coffee mixture, alternately, to the yolk mixture. Fold in one cup finely ground nuts.

Fold gently, into the egg white mixture. Bake at 350 ° for 60 minutes.

Bake in angel-food cake pan. No icing is needed, but can be dusted with powdered sugar.