Mississippi Mud Cake

An offshoot of Mississippi Mud Pie, this rich, dense-dark chocolate cake features a topping of marshmallow, chocolate ganache, and pecans. Although the recipe's original provenance is somewhat murky — it seems to have sprung up simultaneously in various spots around the country in the mid-1970s — it's said that its name might reflect the cake's resemblance to the dense, dark banks of the Mississippi River.

23 mins
30 to 45 mins
1 hr 43 mins
one 9 x 13" cake
Mississippi Mud Cake - select to zoom
Mississippi Mud Cake - select to zoom
Mississippi Mud Cake - select to zoom


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  1. Preheat the oven to 350°F. Grease and flour a 9" x 13" cake pan.

  2. To make the cake: Melt the butter, then stir in the cocoa and hot water.

  3. In a separate bowl, combine the flour, sugar, soda, salt, and espresso powder. Pour the cocoa mixture over the dry ingredients, stirring to blend; the mixture will be a bit lumpy.

  4. Add the sour cream, eggs, and vanilla, beating until nearly smooth; a few small lumps may remain.

  5. Pour the batter into the pan. Bake for 30 to 45 minutes, or until a tester inserted in the center comes out clean. Remove the cake from the oven.

  6. Remove the cake from the oven and wait one minute. Spoon on the marshmallow, wait another 2 minutes, then gently spread the marshmallow over the surface of the cake. Allow to cool to lukewarm, about an hour.

  7. To make the chocolate ganache: Combine the chocolate and cream in a microwave-safe bowl, and heat for 60 to 90 seconds, until the cream is very hot. Stir until the chocolate melts, and keep stirring until the mixture becomes smooth.

  8. Drizzle over the cake. Top with the diced nuts and coconut.

  9. Store, well covered, on the counter for a day, or refrigerate for up to a week.

Tips from our Bakers

  • Instead of using store-bought Marshmallow Fluff or marshmallow creme, try our recipe for your own marshmallow spread.

  • Not interested in making ganache? You can use a premade Hot Fudge Sauce, or use our recipe for delicious Hot Fudge Sauce.