Maya's Chocolate Fudge Flour Sheet Cake

June 11, 2015
6 Ratings
Photo by James Ransom
  • Serves 12
Author Notes

My writing partner and coauthor of Flavor Flours, Maya Klein, created this irresistible American style chocolate cake with knock-your-socks-off milk chocolate frosting. —Alice Medrich

What You'll Need
  • For the chocolate sheet cake:
  • 2 cups (400 grams) sugar
  • 1 1/3 cups (200 grams) white rice flour
  • 1/2 cup (50 grams) oat flour (gluten-free oat flour if gluten is an issue)
  • 2/3 cup (60 grams) natural unsweetened cocoa powder
  • 1/2 teaspoon salt
  • 1/4 teaspoon xanthum gum
  • 1 1/2 teaspoons baking powder
  • 3/4 teaspoon baking soda
  • 2 large eggs
  • 1 cup milk
  • 2 teaspoons pure vanilla extract
  • 1/2 cup neutral flavored vegetable oil (such as corn, safflower, or soybean)
  • 1 cup boiling water
  • For the milk chocolate frosting:
  • 1 cup heavy cream
  • 17 1/2 ounces (500 grams) milk chocolate or 55% to 62% dark chocolate, coarsely chopped
  • 1/4 teaspoon salt, plus more to taste
  • 1/2 pound (225 grams/2 sticks) unsalted butter, very soft
  1. Position a rack in the lower third of the oven and preheat the oven to 350° F. Grease a 9- by 13-inch metal or glass baking pan.
  2. Put the sugar, rice flour, oat flour, cocoa powder, salt, xanthan gum, baking powder, and baking soda in the bowl of the stand mixer and mix with the paddle attachment until well combined. Add the eggs, milk, and vanilla and beat on medium speed for 2 minutes. Add the oil and beat until smooth. Stir in the hot water until well incorporated. The batter will be thin.
  3. Scrape the batter into the pan and bake for 30 to 35 minutes in the metal pan or a little longer in glass, until the cake pulls away slightly from the edges of the pan and a toothpick inserted near the center comes out almost clean. Set the pan on a rack to cool completely before frosting or storing.
  4. Make the frosting: Put the cream, chocolate, and salt in a medium stainless steel bowl. Bring an inch of water to a simmer in a wide skillet.
  5. Turn off the heat and set the bowl of chocolate in the water. Let it rest for 15 minutes, gently shaking the bowl several times to submerge the chocolate in the cream.
  6. When the chocolate is melted, start whisking at one edge and continue whisking until all of the chocolate is incorporated and the mixture is smooth.
  7. Add the butter in chunks and whisk once or twice to break them up; let the mixture rest for 5 minute to finish melting the butter before whisking it smooth. Taste and adjust salt if necessary. Set aside, without mixing or disturbing, until needed.
  8. If the frosting is stiff by the time you need it, set the bowl in a pan of hot water to soften it, stirring occasionally until smooth and just pourable. Scrape the frosting over the cake and spread it evenly. Let set at room temperature, then cover and refrigerate the cake or keep it at room temperature—it‘s great either way. The cake keeps for at least 3 days at room temperature and 5 days in the refrigerator.

See what other Food52ers are saying.

  • Victoria Condon
    Victoria Condon
  • Cel Wise
    Cel Wise
  • Cheryl Maslin
    Cheryl Maslin
  • durun99
  • Alice Ferris
    Alice Ferris
My career was sparked by a single bite of a chocolate truffle, made by my Paris landlady in 1972. I returned home to open this country’s first chocolate bakery and dessert shop, Cocolat, and I am often “blamed” for introducing chocolate truffles to America. Today I am the James Beard Foundation and IACP award-winning author of ten cookbooks, teach a chocolate dessert class on, and work with some of the world’s best chocolate companies. In 2018, I won the IACP Award for Best Food-Focused Column (this one!).

11 Reviews

neshama369 March 21, 2023
Can I sub almond flour?
Dewey S. January 23, 2019
I earmarked this recipe since I have friends who are GF. The grams for the flour blend, particularly the rice flour seems off. On my scale (new, accurate), 100 grams of rice flour came to 1 cup plus 1/4 teaspoon. Thus, 200g is close to 2 cups plus 1/2 teaspoon. If the grams are correct, then the cup volume is not. Grams for oat flour and cocoa are closer, equivalent of 1/2 cup plus 1 tablespoon, and 2/3 cup plus 2 tablespoons, respectively. Please clarify because I'm intrigued by this GF flour blend.
Cel W. February 4, 2019
I use the weights and it comes out perfect every time... I wouldn't stress out on the cups and teaspoons...
Victoria C. January 22, 2018
Milk Substitute for a friend that is dairy and gluten free?
C C. October 18, 2017
This cake is excellent! I tried it with "sweet white rice" flour (Bob's Red Mill) and it was good in a chewy mochi kind of way. Then I tried it with "white rice" flour (Bob's Red Mill) and it was excellent! This is now my family's go to birthday cake. Thank you! Oh, and the frosting is the best ever.
Cel W. September 14, 2017
This cake is so good, I made it for my birthday this week! I went out and bought the book too!
Cheryl M. September 2, 2016
Just to clarify: oats are already 'gluten-free." They become contaminated with gluten as they are frequently processed/transported on conveyors that also carry wheat and other gluten foods, especially by major/conventional brands. Bob's Red Mill brand, however, processes their gluten-free foods on isolated systems away from those with gluten. Or, you can prepare your own fresh oat flour by buying whole oats, which store better in the long run, and whirling them away to a flour in your own food processor. The nutrition is actually more intact rather than fading away in the aftermath of being processed and bagged and on a store shelf for who know how long.
Nastia September 22, 2015
Can it be cooked without xanthan gum? Don't have it in my country unfortunately.
durun99 June 27, 2015
I made this cake for my wife's birthday and it was great, like everything else we've made out of Flavor Flours. (This recipe is just a hair different than the one in the book, which uses 2 teaspoons baking powder & 1 teaspoon baking soda.) I have two comments about the recipe. First, Alice is not kidding when she says the batter is thin; you pour, not scrape, it into the pan. Second, this is a lot of frosting, almost as thick as the cake itself. Everyone in the family agreed we'd only use half a recipe of frosting next time. But it is tasty!
Alice F. June 14, 2015
The recipe is missing a key ingredient...cocoa powder! What's the measure for that?
Cheryl M. September 2, 2016
The recipe above (as I see it today) says 2/3 c. natural unsweetened cocoa powder. I'm guessing that means no alkali process, which would be mentioned on the package.