Fudgy Oat Flour Chocolate Cake – Rich, Moist, and Gluten-Free

This cake is for anyone who craves deep chocolate flavor with a tender, fudgy crumb—and wants a gluten-free option that doesn’t taste “alternative.” It’s simple to make, uses pantry staples, and bakes up beautifully in a single bowl. Oat flour gives it a soft, brownie-like texture without being heavy. You can serve it plain, dusted with cocoa, or with a quick ganache.

It’s the kind of cake you’ll want to make again and again.

Print Recipe

Fudgy Oat Flour Chocolate Cake - Rich, Moist, and Gluten-Free

Prep Time15 minutes mins

Cook Time30 minutes mins

Total Time45 minutes mins

Servings: 8 servings

Ingredients

• Oat flour (store-bought or finely ground rolled oats)
• Unsweetened cocoa powder (Dutch-process or natural)
• Dark chocolate (60–70%), chopped or chips
• Granulated sugar (or coconut sugar)
• Eggs
• Milk (dairy or unsweetened almond milk)
• Neutral oil (avocado, light olive, or canola) or melted butter
• Plain yogurt or sour cream
• Vanilla extract
• Baking powder
• Baking soda
• Fine sea salt
• Optional: Espresso powder, flaky salt, chocolate chips for topping
• Optional ganache: Heavy cream and more dark chocolate

Instructions

• Prep the pan: Heat oven to 350°F (175°C). Grease an 8-inch round or square pan and line the bottom with parchment.
• Melt the chocolate: In a microwave-safe bowl, melt 3 ounces dark chocolate in 20–30 second bursts, stirring until smooth. Set aside to cool slightly.
• Mix the dry ingredients: In a large bowl, whisk 1 1/2 cups oat flour, 1/2 cup cocoa, 1 teaspoon baking powder, 1/2 teaspoon baking soda, and 1/2 teaspoon salt.If using, add 1 teaspoon espresso powder.
• Combine the wet ingredients: Add 3/4 cup sugar, 2 large eggs, 1/3 cup oil, 1/2 cup milk, 1/3 cup yogurt, and 2 teaspoons vanilla to the bowl. Whisk until mostly smooth.
• Stir in the chocolate: Pour in the melted chocolate and stir until the batter is glossy and thick. Avoid overmixing.
• Fill the pan: Scrape the batter into the prepared pan.Smooth the top. Sprinkle on a handful of chocolate chips if you like.
• Bake: Bake 24–30 minutes, until the edges are set and a toothpick comes out with a few moist crumbs. Do not overbake—this keeps the cake fudgy.
• Cool: Let the cake cool in the pan for 15 minutes, then transfer to a rack to cool completely.
• Optional ganache: Warm 1/2 cup heavy cream until steaming. Pour over 4 ounces chopped chocolate and let sit 2 minutes, then stir smooth.Spread over the cooled cake.

What Makes This Recipe So Good

• Fudgy texture: Oat flour locks in moisture, so the cake stays soft and rich.
• Gluten-free without fuss: No blends or gums needed—just pure oat flour.
• Deep chocolate flavor: Cocoa plus melted chocolate makes it taste like a bakery cake.
• One-bowl friendly: Minimal dishes and straightforward steps.
• Flexible sweetness: Works with regular sugar, coconut sugar, or a mix.

Shopping List

• Oat flour (store-bought or finely ground rolled oats)
• Unsweetened cocoa powder (Dutch-process or natural)
• Dark chocolate (60–70%), chopped or chips
• Granulated sugar (or coconut sugar)
• Eggs
• Milk (dairy or unsweetened almond milk)
• Neutral oil (avocado, light olive, or canola) or melted butter
• Plain yogurt or sour cream
• Vanilla extract
• Baking powder
• Baking soda
• Fine sea salt
• Optional: Espresso powder, flaky salt, chocolate chips for topping
• Optional ganache: Heavy cream and more dark chocolate

How to Make It

1. Prep the pan: Heat oven to 350°F (175°C). Grease an 8-inch round or square pan and line the bottom with parchment.
2. Melt the chocolate: In a microwave-safe bowl, melt 3 ounces dark chocolate in 20–30 second bursts, stirring until smooth. Set aside to cool slightly.
3. Mix the dry ingredients: In a large bowl, whisk 1 1/2 cups oat flour, 1/2 cup cocoa, 1 teaspoon baking powder, 1/2 teaspoon baking soda, and 1/2 teaspoon salt.

   If using, add 1 teaspoon espresso powder.

4. Combine the wet ingredients: Add 3/4 cup sugar, 2 large eggs, 1/3 cup oil, 1/2 cup milk, 1/3 cup yogurt, and 2 teaspoons vanilla to the bowl. Whisk until mostly smooth.
5. Stir in the chocolate: Pour in the melted chocolate and stir until the batter is glossy and thick. Avoid overmixing.
6. Fill the pan: Scrape the batter into the prepared pan.

   Smooth the top. Sprinkle on a handful of chocolate chips if you like.

7. Bake: Bake 24–30 minutes, until the edges are set and a toothpick comes out with a few moist crumbs. Do not overbake—this keeps the cake fudgy.
8. Cool: Let the cake cool in the pan for 15 minutes, then transfer to a rack to cool completely.
9. Optional ganache: Warm 1/2 cup heavy cream until steaming. Pour over 4 ounces chopped chocolate and let sit 2 minutes, then stir smooth.

   Spread over the cooled cake.

Storage Instructions

• Room temperature: Keep covered for up to 2 days. The texture stays moist.
• Refrigerator: Store airtight for 4–5 days. Bring to room temp before serving for the best fudginess.
• Freezer: Wrap slices individually and freeze up to 2 months.

  Thaw overnight in the fridge or at room temp for 1–2 hours.

Why This is Good for You

• Whole-grain oats: Oat flour provides fiber and beta-glucan, which supports heart health.
• Balanced fats: Using oil or olive oil keeps the crumb tender and adds unsaturated fats.
• Antioxidants: Cocoa and dark chocolate offer polyphenols that support overall wellness.
• Gluten-free option: Great for those avoiding wheat. Use certified gluten-free oats if needed.

Common Mistakes to Avoid

• Overbaking: Pull the cake when a toothpick shows moist crumbs, not a clean stick.
• Skipping parchment: Oat flour cakes can stick. Line the pan for an easy release.
• Overmixing the batter: Stir until just combined to keep the crumb tender.
• Using overly hot chocolate: Let melted chocolate cool slightly so it doesn’t scramble the eggs.
• Old leaveners: Baking powder and soda lose strength over time.

  Use fresh for a good rise.

Recipe Variations

• Mocha twist: Add 1–2 teaspoons espresso powder to intensify chocolate flavor.
• Orange-chocolate: Stir in 1 tablespoon orange zest and swap vanilla for 1 teaspoon orange extract.
• Peanut butter swirl: Dollop 1/3 cup warmed peanut butter over the batter and swirl with a knife.
• Dairy-free: Use almond milk and dairy-free yogurt. Swap chocolate and ganache for dairy-free versions.
• Extra fudgy: Reduce baking time by 2 minutes and chill the cooled cake for one hour before slicing.

FAQ

Can I make my own oat flour?

Yes. Blend rolled oats in a high-speed blender until very fine and powdery.

Measure after blending for the most accurate amount.

Is this cake gluten-free?

It is if you use certified gluten-free oat flour. Regular oats can be cross-contaminated, so check the label if you’re sensitive.

Can I replace the sugar with honey or maple syrup?

Liquid sweeteners can make the batter too loose. For best texture, use granulated sugar or coconut sugar.

If you must use maple, reduce milk slightly.

What size pan works best?

An 8-inch round or square pan is ideal. A 9-inch pan works too but will bake a bit faster, so start checking a few minutes early.

How do I keep it moist for days?

Don’t overbake, cool completely, and store airtight. A thin ganache or a layer of plastic wrap against the cut surface helps lock in moisture.

Can I make cupcakes?

Yes.

Divide into a 12-cup lined muffin tin and bake 16–20 minutes, checking for moist crumbs.

Wrapping Up

This fudgy oat flour chocolate cake delivers big chocolate flavor with a plush, brownie-like crumb. It’s easy, reliable, and adaptable to whatever you have on hand. Serve it simply or dress it up with ganache—either way, it’s a keeper.

When you want a gluten-free dessert that everyone will love, this one always hits the mark.