Description

This nostalgic buttermilk sheet cake is tender, moist, and topped with a decadent chocolate fudge frosting. Perfect for parties, potlucks, or family gatherings, it’s easy to make and always a crowd-pleaser.

Ingredients

Scale

2 cups (250g) all-purpose flour
1 ½ cups (300g) granulated sugar
1 tsp baking soda
½ tsp salt
½ cup (115g) unsalted butter, melted
½ cup (120ml) neutral oil (canola or vegetable)
1 cup (240ml) buttermilk (full-fat preferred)
2 large eggs, room temperature
2 tsp pure vanilla extract
½ cup (115g) unsalted butter, softened (for frosting)
½ cup (45g) unsweetened cocoa powder
3 cups (360g) powdered sugar, sifted
¼ cup (60ml) buttermilk (for frosting)
2 tsp pure vanilla extract (for frosting)
Pinch of salt (for frosting)
Optional: Chocolate shavings
Optional: Sprinkles
Optional: Chopped toasted pecans or walnuts

Instructions

Preheat oven to 350°F (175°C). Grease or line a 13×9-inch baking pan with parchment paper.
In a large bowl, whisk together flour, sugar, baking soda, and salt until well combined.
In a separate bowl, whisk melted butter, oil, buttermilk, eggs, and vanilla extract until smooth.
Pour wet ingredients into dry ingredients and gently mix until just combined. Do not overmix.
Pour batter into prepared pan and smooth the top with a spatula.
Bake for 28–32 minutes, or until a toothpick inserted in the center comes out clean.
Let cake cool in the pan on a wire rack for at least 30 minutes.
For the frosting: In a medium bowl, beat softened butter until fluffy (about 2 minutes). Add cocoa powder and mix until incorporated.
Gradually add powdered sugar, alternating with buttermilk, beating until creamy and spreadable.
Mix in vanilla extract and a pinch of salt. Frosting should be silky, thick, and glossy.
Spread frosting evenly over cooled cake with an offset spatula.
Add optional toppings: chocolate shavings, sprinkles, or nuts.
Slice into squares and serve at room temperature.

Notes

For gluten-free, use a 1:1 gluten-free flour blend. For dairy-free, substitute plant-based butter and coconut milk with lemon juice for buttermilk. Sift powdered sugar and cocoa for smooth frosting. Chill frosted cake for 10 minutes before slicing for cleaner cuts. Reduce sugar by ¼ cup for less sweetness. Add orange zest, berries, or espresso powder for variations.

Prep Time: 20 minutes
Cook Time: 30 minutes
Category: Dessert
Cuisine: American

Nutrition

Serving Size: 1 square (1/16 of cake)
Calories: 320
Sugar: 30
Sodium: 220
Fat: 14
Saturated Fat: 7
Carbohydrates: 45
Fiber: 2
Protein: 4

Keywords: buttermilk sheet cake, chocolate fudge frosting, easy cake recipe, party dessert, potluck cake, classic sheet cake, moist cake, chocolate cake