Fudgy Chocolate Rhubarb Cookies

If you think rhubarb only belongs in pie, wait until you try these Fudgy Chocolate Rhubarb Cookies. Rich cocoa, melty chocolate chips, and tart rhubarb come together in a soft, brownie-like cookie with chewy centers and slightly crisp edges. The combination may sound unexpected, but one bite will make you wonder why chocolate and rhubarb aren’t paired together more often. 

This cookie recipe is easy to make, packed with chocolate flavor, and a delicious way to use fresh rhubarb during spring and summer. Plus, they can easily be made gluten-free. 

Why You’ll Love These Fudgy Chocolate Rhubarb Cookies

• Rich, fudgy, brownie-like texture
• Sweet chocolate balanced by tart rhubarb
• Easy to make with simple ingredients
• A unique way to use fresh rhubarb
• Gluten-free option included
• Perfect for spring and summer baking

Key Ingredients

Fresh Rhubarb

Rhubarb adds a bright, tart flavor that balances the richness of the chocolate. Finely dicing the rhubarb helps it distribute evenly throughout the cookies.

Cocoa Powder

Unsweetened cocoa powder creates the deep chocolate flavor and contributes to the fudgy texture.

Chocolate Chips

Chocolate chips melt into the cookies, creating pockets of rich chocolate in every bite.

Egg Yolk

An extra egg yolk helps create a chewy, brownie-like center while keeping the cookies soft.

Ingredients for Fudgy Chocolate Rhubarb Cookies

Makes 12 large cookies

• 1/2 cup unsalted butter, softened
• 1/2 cup granulated sugar
• 1/2 cup light brown sugar
• 1 large egg
• 1 large egg yolk
• 1 tablespoon cornstarch
• 1 teaspoon vanilla extract
• 1 1/4 cups all-purpose flour or 1:1 flour (SEE TIPS BELOW TO MAKE THESE GLUTEN-FREE)
• 1/2 cup unsweetened cocoa powder
• 1/2 teaspoon baking soda
• 1/4 teaspoon salt
• 3/4 cup chocolate chips
• 1/2 cup finely diced rhubarb
• 1 teaspoon granulated sugar

Instructions for Fudgy Chocolate Rhubarb Cookies

1. Place the diced rhubarb in a medium bowl and toss with 1 teaspoon sugar. Set aside while preparing the cookie dough.
2. In a large bowl, cream together the butter, granulated sugar, and brown sugar until light and fluffy, about 2 to 3 minutes.
3. Add the egg, egg yolk, vanilla extract, and cornstarch. Mix until smooth and well combined.
4. In a separate bowl, whisk together the flour, cocoa powder, baking soda, salt
5. Gradually add the dry ingredients to the wet ingredients into the batter, mixing just until combined. Do not overmix.
6. Blot the rhubarb with paper towels to remove excess moisture. Stir in the rhubarb and chocolate chips into the dough.
7. Cover and chill dough for at least 1 hour.
8. Preheat the oven to 350°F. Line baking sheets with parchment paper.
9. Scoop large portions of dough onto the prepared cookies sheets, spacing them about 2 inches apart.
10. Bake for 11 to 13 minutes, or until the edges are set and the centers still look slightly underbaked.
11. Allow the cookies to cool on the baking sheet for 10 minutes before transferring to a wire rack to cool completely.

Gluten-Free Option

These cookies can easily be made gluten-free by substituting Bob’s Red Mill Gluten Free 1-to-1 Baking Flour for the all-purpose flour.

Gluten-Free Tips

• Use 1 1/4 cups Bob’s Red Mill Gluten Free 1-to-1 Baking Flour.
• Chill the dough for at least 1 hour before baking.
• If the dough seems dry after mixing, add 1 tablespoon milk.
• Let the cookies cool completely before serving.
• The cookies are often even fudgier the next day once the flour has fully hydrated.

More gluten-free cookies

Banana Crumb Cookies

Oatmeal Chocolate Chip Cookies

 

What Does Rhubarb Taste Like?

Rhubarb has a bright, tart flavor often compared to green apples or sour berries. While it’s most commonly paired with strawberries, it pairs surprisingly well with chocolate. The tangy rhubarb balances the richness of the cocoa, creating a cookie that’s sweet, fudgy, and just a little tart.

Storage Tips for Chocolate Rhubarb Cookies

Store cookies in an airtight container at room temperature for up to 4 days.

For longer storage, freeze baked cookies in a freezer-safe container for up to 3 months.

Frequently Asked Questions

Can I use frozen rhubarb?

Yes. Thaw the rhubarb completely and blot away excess moisture before adding it to the dough.

Can I make these cookies gluten-free?

Yes. Substitute Bob’s Red Mill Gluten Free 1-to-1 Baking Flour for the all-purpose flour and follow the gluten-free tips above.

Why aren’t my cookies fudgy?

Overbaking is the most common cause. Remove the cookies when the centers still look slightly underbaked. They will continue to set as they cool.

Can I freeze the cookie dough?

Yes. Scoop the dough into cookie portions and freeze for up to 3 months. Bake directly from frozen, adding 1 to 2 minutes to the baking time.

Can I use white chocolate chips?

Absolutely. White chocolate chips pair beautifully with the tart rhubarb and create a sweeter cookie.

More Rhubarb Recipes