Thank you so much for stopping by! Truly—it means a lot to share recipes like this with you. This Moist Rhubarb Cake is something really special: it’s the kind of old-fashioned, soul-soothing dessert that tastes like it came straight from grandma’s kitchen (but with way less fuss). Tart rhubarb folded into a tender, cinnamon-kissed crumb and finished with a sugary crackle topping? Yes, please!

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What Is Moist Rhubarb Cake?

This cake is a simple one-bowl, no-frosting-needed wonder. Chopped fresh rhubarb is folded into a vanilla-scented batter enriched with buttermilk and oil—two key ingredients that guarantee a soft, ultra-moist crumb. It’s topped with a generous sprinkle of cinnamon sugar that bakes into a delicate crust, giving every bite a perfect sweet-tart balance and a touch of crunch on top.

It’s the perfect spring dessert to bring to a potluck, serve with coffee, or sneak a slice of for breakfast. (And yes, it gets even better the next day.)

Why You’ll Love This Moist Rhubarb Cake

Incredibly soft and moist thanks to buttermilk and oil
Tart-sweet perfection from juicy rhubarb and a sugary topping
Quick and easy – just one bowl and no mixer needed
No frosting required! It’s already deliciously complete
Great for make-ahead – stays moist for days

What Does This Rhubarb Cake Taste Like?

Every forkful is a little sweet, a little tangy, and totally comforting. The rhubarb softens as it bakes, creating pockets of brightness that play beautifully against the vanilla cake base. A hint of cinnamon in the topping adds warmth, and that sugar crust? Chef’s kiss.

Imagine coffee cake meets fruit cobbler… but in sliceable, snackable form.

Healthier Highlights

While this is definitely a treat, here are a few little wins:

No butter – it uses oil for moisture
Lower sugar than many cakes – with big flavor payoff
Uses fresh seasonal produce – rhubarb is low in calories and high in fiber
No frosting needed – less sugar, less effort, and still perfect

Ingredients

For the Cake:

1 ½ cups chopped fresh rhubarb (about 2–3 stalks)
1 ½ cups all-purpose flour
1 cup granulated sugar
½ teaspoon salt
1 teaspoon baking soda
1 teaspoon vanilla extract
½ cup vegetable oil (or melted coconut oil)
1 egg
1 cup buttermilk (or 1 cup milk + 1 tbsp lemon juice)

For the Topping:

¼ cup sugar
½ teaspoon cinnamon

Tools You’ll Need

Mixing bowls
9×13 inch baking pan or 8×8 for a thicker cake
Whisk and rubber spatula
Measuring cups and spoons
Knife and cutting board

Ingredient Additions & Substitutions

Add fruit: Sub in half strawberries for a rhubarb-strawberry twist
No buttermilk? Make your own with milk + lemon juice or vinegar
Make it whole grain: Use half whole wheat flour for extra fiber
Gluten-free version: Use a 1:1 gluten-free flour blend
Love nuts? Add chopped walnuts or pecans to the batter or topping for crunch
Try coconut sugar for a deeper, caramel-like sweetness

How to Make Moist Rhubarb Cake

1. Preheat and prepare

Preheat your oven to 350°F (175°C). Grease or line a 9×13 inch pan with parchment paper.

2. Mix the dry ingredients

In a large bowl, whisk together flour, sugar, salt, and baking soda.

3. Add the wet ingredients

Stir in the oil, egg, vanilla, and buttermilk. Mix until just combined—don’t overdo it!

4. Fold in the rhubarb

Gently stir in the chopped rhubarb until evenly distributed.

5. Pour and top

Spread the batter into the prepared pan. In a small bowl, mix the sugar and cinnamon for the topping. Sprinkle evenly over the top of the batter.

6. Bake

Bake for 35–40 minutes or until a toothpick comes out clean. Let cool in the pan before slicing. (Try not to eat it all warm from the pan… or do!)

What to Serve with Rhubarb Cake

This Moist Rhubarb Cake is perfectly delightful on its own, but if you want to dress it up for guests—or just treat yourself to something a little extra—here are some serving ideas to make it even more memorable:

☕️ For a Cozy Coffee Break
- Hot coffee or tea – The slight bitterness of coffee or the floral notes of a black tea beautifully balance the sweet-tart flavor of the cake. Earl Grey or Darjeeling are personal favorites here!
🍨 For a Dessert Upgrade
- Vanilla ice cream – Cold, creamy vanilla is the perfect contrast to the warm, tender crumb of the cake. Bonus: it turns the cake into a rustic but elegant dessert.
- Whipped cream – Light and airy, a dollop of whipped cream adds richness without overpowering the rhubarb.
- Crème fraîche or Greek yogurt – A tangy counterpoint that plays up the rhubarb’s tartness and adds a little sophistication.
🍓 For a Springtime Brunch
- Fresh berries – Strawberries, raspberries, or blueberries pair beautifully with the tart rhubarb and add a burst of juicy sweetness.
- Citrus zest – A sprinkle of lemon or orange zest over each slice can brighten and lift the entire flavor profile.
🧀 For a Sweet & Savory Combo
- Soft cheeses like mascarpone or brie – For a decadent appetizer or brunch board, serve small squares of the cake with soft cheese and a drizzle of honey. Trust me—people love it.
Whether you’re enjoying it as a quiet afternoon treat or serving it at your next spring gathering, this rhubarb cake is flexible, unfussy, and always a hit.

Would you like a printable brunch menu featuring this cake?

Tips for the Best Rhubarb Cake

Don’t overmix! Stir until the batter just comes together—this keeps the cake tender.
Use fresh rhubarb. The tartness pops best when it’s in season (April–June).
Toss rhubarb with a teaspoon of flour before folding it in—this keeps it from sinking.
Let it rest before slicing. The crumb sets up nicely as it cools and gets easier to cut.
Store at room temp covered with foil or in an airtight container to keep it moist.

Storage Instructions

One of the best things about this Moist Rhubarb Cake—besides how delicious it is—is how well it keeps! Whether you’re enjoying a slice fresh from the oven or saving a few for later, here’s how to store it to maintain that tender crumb and bright rhubarb flavor:

🕒 Room Temperature
- Best for short-term storage (1–2 days).
- Once completely cooled, cover the cake tightly with plastic wrap, foil, or store in an airtight container. Keep it in a cool, dry spot on your counter.
- Pro tip: If you live in a humid climate, storing in the fridge may be a better option to prevent spoilage.
❄️ Refrigerator
- Keeps well for up to 5 days.
- Place cake slices in an airtight container or wrap them individually to retain moisture.
- Bring to room temperature or warm slightly in the microwave before serving—this softens the crumb and brings the flavor back to life.
🧊 Freezer
- Freeze for up to 3 months!
- Cool the cake completely, then wrap individual slices tightly in plastic wrap and place them in a freezer-safe bag or container.
- To thaw, leave slices at room temperature for about 30–45 minutes or warm gently in the microwave or oven.
- Tip for success: Freeze in slices for easy portion control and on-demand dessert moments.
This cake is just as delightful on day three as it is fresh out of the oven—maybe even better. The flavors meld, and the crumb stays super soft. Want a printable freezer label or reheating cheat sheet? I can create that for you!

General Information

Here’s a quick-reference guide to all the essential details you need for making and enjoying this Moist Rhubarb Cake:

Prep Time: 15 minutes

Bake Time: 35–40 minutes

Total Time: 50–55 minutes

Yield: One 9×13-inch cake (about 12–15 servings)

Skill Level: Beginner-friendly – easy to make with simple ingredients

Best Season to Make: Spring and early summer (April to June, when rhubarb is in season)

Freezer-Friendly: Yes – freezes beautifully in individual slices

Storage: Keeps 2–3 days at room temperature, up to 5 days in the fridge, or 3 months in the freezer

Vegetarian: Yes

Kid-Friendly: Absolutely – sweet with just enough tang!

Great For: Potlucks, picnics, bake sales, brunch, or an easy weeknight dessert

This is one of those timeless recipes you’ll find yourself reaching for again and again—especially when rhubarb season rolls around and you need something that’s just the right mix of sweet, tart, and nostalgic.

Would you like a downloadable PDF version of this recipe or a printable kitchen tip card?

Frequently Asked Questions

Can I use frozen rhubarb?

Yes! Just thaw and pat dry before adding to the batter—too much moisture can make the cake gummy.

Can I reduce the sugar?

You can cut the sugar in the batter by 1/4 cup if you prefer it less sweet. Just note the cake will be more tart.

What can I use instead of buttermilk?

Mix 1 tablespoon of lemon juice or vinegar into 1 cup of milk. Let it sit for 5 minutes before using—it works beautifully!

Is this cake good for breakfast?

Absolutely! It’s soft, not too sweet, and pairs perfectly with a morning cup of coffee.

Conclusion

This Moist Rhubarb Cake is everything a great spring dessert should be—easy, comforting, and absolutely full of flavor. The kind of cake that disappears from the pan way too fast, and leaves you already planning your next batch.

Whether you’re new to rhubarb or a longtime fan, this recipe brings out the best in this tart little stalk. Make it for a gathering, a bake sale, or just because it’s Tuesday and you deserve a treat!

Love rhubarb as much as I do? Try these next:

Rhubarb Crumb Bars
Strawberry Rhubarb Galette
Rhubarb Muffins with Streusel Topping

Share Your Slice!

Made this cake? I’d love to see how it turned out! Tag your photos on Pinterest or drop a comment below—your bakes always make my day. 💕

Nutritional Information (per slice, based on 12 servings)

Calories: 260
Carbohydrates: 35g
Sugar: 20g
Protein: 3g
Fat: 11g
Saturated Fat: 1g
Fiber: 1g
Sodium: 190mg