Rhubarb Cake with Vanilla Butter Sauce Recipe

If rhubarb were a person, it would be that quirky neighbor who shows up with strange gifts but somehow steals the show at every party. It’s tart, loud, and impossible to ignore. So what do we do? We throw it into a cake, pour warm vanilla butter sauce over the top, and call it a masterpiece. This recipe balances sweet and tangy like a gymnast doing a cartwheel on a lemon.

What You Need

For the cake

• 2 cups chopped fresh rhubarb
• 1½ cups brown sugar
• ½ cup vegetable oil
• 1 egg
• 1 teaspoon vanilla extract
• 1 cup buttermilk
• 2 cups all-purpose flour
• 1 teaspoon baking soda
• ½ teaspoon salt

For the sauce

• 1 cup sugar
• ½ cup butter
• ½ cup heavy cream
• 1 teaspoon vanilla extract

What to Do

Preheat the oven to 350°F. Grease a 9×13-inch baking pan. Don’t forget the corners. Cakes hate dry corners.

In a large bowl, mix brown sugar, oil, egg, and vanilla. Stir until smooth. Add buttermilk. Mix again. If your arm isn’t tired yet, you’re doing great.

In another bowl, mix flour, baking soda, and salt. Add this to the wet mix. Stir until combined. Gently fold in the chopped rhubarb. No need to wrestle it.

Pour the batter into the greased pan. Spread evenly. Bake for 40 to 45 minutes or until a toothpick comes out clean. Resist the urge to poke it every five minutes.

While the cake bakes, make the sauce. In a small saucepan, melt butter over medium heat. Add sugar and cream. Stir until smooth. Let it simmer for about 3 minutes. Stir often so it doesn’t burn. Remove from heat. Add vanilla. Stir again. Try not to drink it.

Let the cake cool slightly. Serve warm slices with a generous spoonful of the vanilla butter sauce. Add more sauce if someone is watching. That’s called sharing.

Final Thoughts

This rhubarb cake is sweet, simple, and slightly dramatic—like a soap opera in dessert form. It’s easy to make, hard to resist, and perfect for anyone who likes their fruit with a bit of sass.

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Rhubarb Cake with Vanilla Butter Sauce

It’s a breeze to whip up, impossible to ignore, and an absolute must for anyone who loves their desserts with a little zing. Tart, tender, and totally irresistible—this cake is the star of the show! ✨🍰

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Ingredients

For the cake:

• 2 cups chopped fresh rhubarb
• 1½ cups brown sugar
• ½ cup vegetable oil
• 1 egg
• 1 teaspoon vanilla extract
• 1 cup buttermilk
• 2 cups all-purpose flour
• 1 teaspoon baking soda
• ½ teaspoon salt

For the sauce

• 1 cup sugar
• ½ cup butter
• ½ cup heavy cream
• 1 teaspoon vanilla extract

Instructions

1. Prep: Preheat oven to 350°F. Grease a 9x13-inch pan, including corners.
2. Wet mix: In a large bowl, combine brown sugar, oil, egg, and vanilla. Mix until smooth. Stir in buttermilk.
3. Dry mix: In another bowl, whisk flour, baking soda, and salt. Add to wet mix and stir just until combined. Fold in chopped rhubarb.
4. Bake: Pour batter into pan, spread evenly, and bake 40–45 min, until a toothpick comes out clean.
5. Sauce: Melt butter in a saucepan. Add sugar and cream, stir until smooth. Simmer 3 min, stirring often. Remove from heat, add vanilla.
6. Serve: Let cake cool slightly. Drizzle warm slices with sauce. Extra sauce encouraged.