Rhubarb Cake with Butter Sauce

• Prep Time: 20 minutes

• Cook Time: 45–50 minutes

• Butter Sauce Cook Time: 5–7 minutes

• Cooling Time: 15 minutes

• Total Time: About 1 hour 25 minutes

• Skill Level: Easy to Moderate

• Servings: 12

• Best Served: Warm with sauce poured over

Ingredients

For the Rhubarb Cake:

• 1 ½ cups (300g) granulated sugar

• ½ cup (115g) unsalted butter, softened

• 1 large egg

• 1 tsp pure vanilla extract

• 2 cups (250g) all-purpose flour

• 1 tsp baking soda

• ½ tsp salt

• 1 cup (240ml) buttermilk

• 2 cups (about 230g) diced rhubarb (fresh or frozen, thawed and drained if using frozen)

Optional Topping (before baking):

• 2 tbsp granulated sugar

• ½ tsp cinnamon

For the Butter Sauce:

• ½ cup (115g) unsalted butter

• ¾ cup (150g) granulated sugar

• ½ cup (120ml) heavy cream or evaporated milk

• 1 tsp vanilla extract

Kitchen Tools Needed

• 9×13-inch baking pan

• Mixing bowls

• Hand mixer or stand mixer

• Whisk and rubber spatula

• Measuring cups and spoons

• Small saucepan (for sauce)

• Wooden spoon

Intensity & Pro Tips

• Intensity:  Easy to Moderate. The cake itself is very simple; the sauce requires basic stovetop technique. Great for beginner bakers with a little kitchen confidence.

Tips:

• If you don’t have buttermilk, make your own by combining 1 tbsp vinegar or lemon juice with 1 cup milk. Let sit 5 minutes before using.

• For more flavor, toss rhubarb with 1 tbsp sugar before folding into the batter.

• The butter sauce can be doubled if you want leftovers (it’s amazing over ice cream too!).

Instructions Step 1: Prepare Your Oven and Pan

• Preheat oven to 350°F (175°C).

• Grease a 9×13-inch baking pan (you can line it with parchment for easier cleanup).

 Step 2: Cream Butter and Sugar

• In a large bowl, beat ½ cup softened butter and 1½ cups sugar together using a hand or stand mixer. Beat for about 2–3 minutes until light and fluffy.

• Add 1 large egg and 1 tsp vanilla extract, and beat until smooth and well incorporated.

 Step 3: Mix Dry Ingredients

• In a separate bowl, whisk together:

  • 2 cups flour

  • 1 tsp baking soda

  • ½ tsp salt

 Step 4: Combine Wet and Dry Ingredients

• With the mixer on low speed, alternate adding the flour mixture and 1 cup buttermilk into the butter mixture. Start and end with flour (flour → buttermilk → flour → buttermilk → flour).

• Mix until just combined — do not overmix.

Step 5: Fold in Rhubarb

• Gently fold in 2 cups chopped rhubarb using a rubber spatula. Distribute evenly throughout the batter.

 Step 6: Pour and Add Topping

• Spread the batter evenly into the prepared 9×13-inch pan.

• Optional: Mix 2 tbsp sugar with ½ tsp cinnamon and sprinkle over the top before baking for a subtle crusty finish.

 Step 7: Bake

• Bake in preheated oven for 45 to 50 minutes, or until a toothpick inserted in the center comes out clean.

• Allow to cool for at least 15 minutes before serving. The cake can be served warm or at room temperature.

Butter Sauce Instructions

While the cake cools, make the sauce:

 Step 1: Melt Butter

• In a small saucepan over medium heat, melt ½ cup butter.

 Step 2: Add Sugar and Cream

• Stir in ¾ cup sugar and ½ cup heavy cream (or evaporated milk). Bring to a low simmer, stirring constantly.

 Step 3: Simmer

• Allow to simmer gently for 5–7 minutes, stirring occasionally, until it slightly thickens and sugar is dissolved.

 Step 4: Add Vanilla

• Remove from heat and stir in 1 tsp vanilla extract.

Note: The sauce will be thin — it’s meant to soak into the cake.

How to Serve

• Cut cake into squares.

• Serve warm or room temperature.

• Drizzle warm butter sauce over each slice just before serving.

• Add a scoop of vanilla ice cream or a dollop of whipped cream for extra indulgence.

Nutritional Information

(Estimated per serving, based on 12 servings including butter sauce)

Note: These values are estimates and can vary depending on exact ingredients and brands used.