Diana, I remembered your request for a German Applesauce Cake when I came across a recipe tonight from TV's Chef Tell Erhardt that was published in a 1982 cookbook entitled "Culinary Gems from the Diamond State" that benefited Delaware's Division of The American Cancer Society. At that time he did local cooking segments on KYW-TV in Philadelphia, PA. This does say apple cake but appears to be an apple/cream-filled pastry. On the off-chance this is what you're looking for, here goes:

Chef Tell Erhardt’s German Apple Cake

1-1/2 cups granulated sugar, divided
2 cups butter or margarine, softened
3 cups all-purpose flour
3 eggs, divided
4 or 5 large baking apples
1/2 cup unseasoned breadcrumbs
1/2 cup heavy cream
Juice of 1 lemon
1 tablespoon cornstarch
1/4 teaspoon vanilla extract
1 cup sour cream
1/2 cup apricot preserves, heated

Combine 1 cup sugar, butter, flour and 1 egg together quickly to form a dough. DO NOT OVERWORK OR YOUR PASTRY WILL BE TOUGH. Cover and refrigerate for at least 1 hour before using. When the pastry has chilled, begin to prepare the filling.

Peel the apples, core them and cut in half. Score the apples on the rounded sides and set aside. Butter and flour a 9” springform pan. Press the chilled dough into the prepared pan to cover the bottom and halfway up the sides. Sprinkle breadcrumbs evenly over the crust. Put the prepared apples in the pan rounded side up. Fill the spaces with pieces of apple.

Mix the cream, lemon juice, 2 eggs, cornstarch, 1/2 cup sugar, vanilla and sour cream together in a bowl. Beat with a whisk to blend well. Pour the cream mixture over the apples and bake at 375 degrees for 1 to 1-1/2 hours, or until apples are tender and the filling is set. Cool slightly and brush top of cake with warm apricot preserves.

Note: You will have about twice as much dough as needed. Don’t try to cut the recipe in half; any leftover dough will keep for at least a week refrigerated if you cover it tightly.