Rhubarb Cake with Cake Mix Made Easy

Here’s my go-to rhubarb cake recipe that starts with a simple cake mix – it’s one of those shortcuts that actually works! The tart rhubarb pairs perfectly with the sweet cake base, and the whole thing comes together in just minutes.

This cake has become a spring tradition in our house, especially when the rhubarb starts popping up in gardens and markets. I often make an extra one to share with neighbors, and somehow it disappears just as quickly as the first!

What Kind of Rhubarb Should I Use?

For this cake recipe, you can use either fresh or frozen rhubarb stalks – both will give you great results. If you’re using fresh rhubarb, look for stalks that are firm and crisp, with a bright pink to red color, though the green parts are just as tasty and perfectly fine to use. When preparing your rhubarb, make sure to remove all the leaves (they’re not edible) and cut the stalks into small, even pieces about 1/4 to 1/2 inch in size so they cook evenly in the cake. If you’re working with frozen rhubarb, thaw it completely and drain off any excess liquid before adding it to your cake mix to prevent your cake from becoming too wet.

Options for Substitutions

This easy rhubarb cake can be adapted with several simple substitutions:

• Yellow cake mix: While yellow cake mix works best, you can use white cake mix or vanilla cake mix instead. Just keep in mind that the color will be slightly different.
• Rhubarb: If fresh rhubarb isn’t available, you can use frozen rhubarb – just thaw and drain it well first. In a pinch, tart apples or strawberries can work too, though this will change the classic flavor profile.
• Vegetable oil: Feel free to swap in canola oil, melted coconut oil, or even unsweetened applesauce (use the same amount) for a lighter version.
• Heavy cream: You can substitute heavy cream with half-and-half, though the topping won’t be quite as rich. For a dairy-free version, full-fat coconut cream can work, but expect a slight coconut flavor.
• Granulated sugar: Regular granulated sugar works best here, but you could use caster sugar or even brown sugar – though brown sugar will add a slight caramel note to the flavor.

Watch Out for These Mistakes While Baking

The biggest challenge when baking with rhubarb is managing its moisture content – chopping the rhubarb too finely can release excess liquid and make your cake soggy, so aim for pieces about 1/2 inch in size.

A common mistake is skipping the sugar coating on the rhubarb, but this step is crucial as it helps balance the tartness and prevents the pieces from sinking to the bottom of the cake.

Temperature control matters more than you might think – starting with room temperature eggs and properly preheated oven (usually 350°F) will help your cake rise evenly and prevent a dense, gummy texture.

For the best texture, avoid overmixing the cake batter once you’ve added the rhubarb – just fold it in gently until barely combined, and remember to check for doneness with a toothpick in the center rather than relying solely on baking time.

What to Serve With Rhubarb Cake?

This sweet-tart rhubarb cake is perfect for afternoon tea or as a dessert, and there are several tasty ways to serve it! A scoop of vanilla ice cream is my go-to choice, as it melts slightly into the warm cake and creates an amazing creamy contrast to the tart rhubarb. If you’re serving it for coffee time, a dollop of freshly whipped cream and a hot cup of coffee or tea makes for a cozy pairing. For an extra special touch, try serving each slice with a drizzle of warm caramel sauce or a sprinkle of powdered sugar on top – both complement the natural tartness of the rhubarb beautifully.

Storage Instructions

Keep Fresh: This rhubarb cake stays moist and yummy when kept in an airtight container at room temperature for up to 3 days. If you live somewhere humid, it’s better to pop it in the fridge where it’ll stay fresh for up to 5 days. Just make sure to cover it well to prevent it from drying out or absorbing other flavors.

Freeze: Good news – this cake freezes really well! Cut it into individual slices, wrap each piece in plastic wrap, and place them in a freezer bag. It’ll keep for up to 3 months. This way, you can grab a slice whenever you’re craving something sweet!

Thaw & Serve: When you’re ready for a piece of cake, just take a slice out of the freezer and let it thaw on the counter for about 1-2 hours. If you want it slightly warm, pop it in the microwave for 15-20 seconds. The cream topping might change texture a bit after freezing, so you might want to add a fresh dollop when serving.

Preparation Time	15-20 minutes
Cooking Time	40-45 minutes
Total Time	55-65 minutes
Level of Difficulty	Easy

Estimated Nutrition

Estimated nutrition for the whole recipe (without optional ingredients):

• Calories: 2400-2600
• Protein: 30-35 g
• Fat: 120-130 g
• Carbohydrates: 350-370 g

Ingredients

For the cake:

• 3 eggs
• 1/3 cup vegetable oil
• 1 cup water
• 1 pkg yellow cake mix

For the rhubarb topping:

• 1 1/4 cups granulated sugar (Nellie & Joe’s is my go-to)
• 2 cups chopped rhubarb (about 1/2-inch pieces)

For the drizzle:

• 1/2 pint heavy cream (for a luscious, pourable topping)

Step 1: Prepare the Baking Pan and Preheat the Oven

Start by preheating your oven to 350 degrees F (175 degrees C).

While the oven is heating up, grease and flour a 9×13-inch baking pan to ensure the cake doesn’t stick and will come out easily after baking.

Step 2: Mix the Cake Batter

In a large bowl, combine the cake mix, water, eggs, and oil.

Use an electric mixer on low speed to blend the ingredients until they are just moistened.

Then, increase the speed to medium and beat for 2 more minutes to create a smooth batter.

Pour the prepared batter into your greased and floured baking pan.

Step 3: Add the Rhubarb and Cream Topping

In a separate bowl, mix together the rhubarb and sugar.

Once combined, spoon this mixture evenly over the cake batter in the pan.

Finally, drizzle whipping cream over the top of the rhubarb and cake batter, distributing it as evenly as possible to ensure all areas get some delicious creaminess.

Step 4: Bake the Cake

Place the pan in your preheated oven and bake for approximately 40 minutes.

The cake is done when a toothpick inserted into the center comes out clean.

This is a good indication that the cake is fully baked through.

Step 5: Cool and Serve

After baking, allow the cake to cool completely in the pan.

Once cooled, carefully turn the cake out onto a serving dish for presentation.

Slice and enjoy your delicious rhubarb-topped cake with friends and family!