Updated Tunnel of Fudge Cake

By
Linda Larsen
Linda Larsen
Linda Larsen is a journalist, quick-cooking and slow-cooking expert, and accomplished cookbook author with over 30 years of experience in testing and developing recipes.
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Updated on 05/5/22
Tunnel of Fudge Cake
Annabelle Breakey/Photolibrary/Getty Images
Prep: 25 mins
Cook: 48 mins
Total: 73 mins
Servings: 16 servings
Yield: 1 cake

You can make the original tunnel of fudge cake using frosting mix, or try this updated recipe made from scratch. The confectioners' sugar and cocoa in this recipe essentially replace the frosting mix.

Be sure you follow this recipe exactly as written. Do not substitute any ingredients and be sure you use the full amount of nuts, otherwise, the recipe will fail.

This fabulous cake is so delicious. The soft tunnel of fudge is such a nice surprise. Because the cake is so rich, you don't need to add the frosting if you don't want to.

Ingredients

  • 1 1/2 cups (12 ounces) unsalted butter, softened

  • 1 cup white sugar

  • 3/4 cup packed brown sugar

  • 2 (1-ounce) squares unsweetened chocolate, melted and cooled

  • 6 large eggs, room temperature

  • 2 cups sifted confectioners' sugar

  • 2 cups all-purpose flour

  • 2/3 cup cocoa

  • 2 teaspoons pure vanilla extract

  • 2 cups chopped pecans, or walnuts

For the Glaze:

  • 1/2 cup semisweet chocolate chips

  • 1 teaspoon vegetable oil

Steps to Make It

  1. Heat oven to 350 F.

  2. Measure flour by lightly spooning the flour into the measuring cup, NOT by scooping the measuring cup into the flour. The scoop-and-level method is incorrect and will make this cake too dry.

  3. In a large bowl, combine butter, white sugar and brown sugar and beat until mixture is light and fluffy. Add melted and cooled chocolate, beating until combined.

  4. Add eggs, one at a time, beating thoroughly after each addition until eggs combine with butter mixture (this can take some time).

  5. Sift the confectioners' sugar BEFORE you measure it. Gradually add it to the batter, mixing well. By hand, stir in flour, cocoa, vanilla, and pecans until well blended.

  6. Spray a 12-cup Bundt pan with nonstick baking spray combined with flour. Spoon batter into prepared pan. Bake at 350 F for 48 to 54 minutes, until crust looks dry and shiny (traditional doneness tests won't work because of the soft fudge center).

  7. Cool cake in pan on a rack for 1 hour, then invert onto serving plate and remove pan. Cool completely. If you bake the cake for a shorter period of time, it will have true fudge in the center. Bake it longer for a moist tunnel in the center.

  8. Make the glaze by placing the chocolate chips and oil in a small microwave-safe bowl. Microwave on 50 percent power for 2 minutes and then stir. Continue microwaving until chocolate is melted and the mixture is smooth.

  9. Pour into a small zip-top bag. Cut a tiny piece off the corner of the bag and pipe the chocolate over the cake, using a back-and-forth motion. Let cool.

Tips

  • Make sure you measure the flour correctly for this recipe.
  • Don't skimp on the walnuts; they're critical to the cake structure.
  • And don't overbake the cake or it might be dry and fall apart.
Nutrition Facts (per serving)
531 Calories
33g Fat
55g Carbs
7g Protein
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Nutrition Facts
Servings: 16
Amount per serving
Calories 531
% Daily Value*
Total Fat 33g 42%
Saturated Fat 15g 73%
Cholesterol 116mg 39%
Sodium 168mg 7%
Total Carbohydrate 55g 20%
Dietary Fiber 3g 12%
Total Sugars 38g
Protein 7g
Vitamin C 0mg 1%
Calcium 40mg 3%
Iron 3mg 19%
Potassium 166mg 4%
*The % Daily Value (DV) tells you how much a nutrient in a food serving contributes to a daily diet. 2,000 calories a day is used for general nutrition advice.
(Nutrition information is calculated using an ingredient database and should be considered an estimate.)