My husband was posting some books on his e-bay site and he brought in a Diamond Walnut recipe booklet which I have now claimed as my own. Diamond Walnut Recipe Favorites is from 1978 and has lots of really good sounding baking recipes. Here is the blurb for the muffin recipe: "A festive surprise awaits when you bite into these two-toned muffins. Bright cherries in light batter highlight one side, while the other half is dark and chocolately. Both halves are crunchy with crisp walnuts."
Chocolate Cherry Marble Muffins
2 cups sifted flour
1/2 cup granulated sugar
3 teaspoons baking powder
1 teaspoon salt
1 large egg, beaten
3/4 cup milk
1/3 cup oil
2/3 cup chopped Diamond Walnuts
1/4 cup chopped maraschino cherries
1/4 cup sweetened cocoa mix
Resift flour with next 3 ingredients. Combine egg, milk and oil; stir into dry mixture only until moistened. Fold in walnuts. Divide into 2 portions; stir cherries into one and spoon into one side of 14 greased 2 1/2-inch muffin pans. Stir cocoa mix into remaining batter and fill other side of pans. Bake at 400 degrees for 20 minutes. Sprinkle with powdered sugar. Serve warm.