Rich Milk Chocolate Sheet Cake with Creamy Chocolate Frosting
A decadently moist chocolate sheet cake made with bittersweet chocolate chips and Dutch cocoa powder, creating deep chocolate flavor in every bite. The cake gets its tender crumb from melting chocolate directly into warm milk, while the silky milk chocolate frosting adds a smooth contrast to the rich base. Perfect for feeding a crowd at birthdays, potlucks, or family gatherings where you need a show-stopping dessert that's easier than layer cakes but just as impressive. The combination of bittersweet and milk chocolates creates complex flavor depth that chocolate lovers will crave.
Ingredients
- vegetable oil spray
- 1 ½ cups sugar
- 1 ¼ cups all-purpose flourgluten-free flour blend1:1gluten-freegluten-free
Works well with cup-for-cup blends
- ½ teaspoon baking soda
- ½ teaspoon salt
- 1 ⅓ cups bittersweet chocolate chipsdairy-free dark chocolate1:1dairy-free
Check label to ensure no milk ingredients
- 1 cup whole milk
- ¾ cup Dutch-processed cocoa powder
- ⅝ cup vegetable oil
- 4 large eggs
- 1 teaspoon vanilla extract
- 1 ⅓ cups milk chocolate chips or 8 oz chopped milk chocolate
- ⅓ cup heavy creamcoconut cream1:1dairy-freedairy-free
Use thick cream from top of chilled coconut milk can
Full guide → - 8 tablespoons unsalted butter, cut into eight pieces and softened
Instructions
- 1
Adjust oven rack to middle position and heat oven to 325 degrees
- 2
Spray 13-by-9-inch metal baking pan with vegetable oil spray
- 3
Whisk together sugar, flour, baking soda and salt in medium bowl
- 4
Combine bittersweet chocolate chips, milk and cocoa in large saucepan
- 5
Place saucepan over low heat and cook, whisking often, until chocolate chips are melted and mixture is smooth
- 6
Remove saucepan from heat and let mixture cool slightly
- 7
Add oil, eggs and vanilla to saucepan with chocolate mixture and whisk until smooth
- 8
Add flour mixture and whisk until smooth, scraping corners of saucepan
- 9
Scrape batter into greased baking pan and smooth top
- 10
Bake until toothpick inserted in center comes out with few crumbs attached
- 11
Remove from oven and place on cooling rack
- 12
Allow cake to cool completely in pan
- 13
Combine milk chocolate chips and cream in large microwave-safe bowl
- 14
Heat in microwave at 50 percent power for 1 minute
- 15
Stir with rubber spatula
- 16
Heat in microwave at 50 percent power until melted
- 17
Add softened butter to chocolate mixture and whisk to break up large pieces
- 18
Let sit until butter is fully melted
- 19
Whisk until completely smooth
- 20
Refrigerate frosting until cooled and thickened
- 21
Beat frosting with electric mixer on medium-high speed until light and fluffy
- 22
Spread frosting evenly over cooled cake
- 23
Cut into pieces and serve
Tips
Let the chocolate mixture cool slightly before adding eggs to prevent them from scrambling and creating lumps in your batter.
Refrigerate the frosting until properly thickened before beating - this creates the light, fluffy texture that spreads beautifully.
Use a toothpick to test doneness, looking for just a few moist crumbs rather than completely clean for the most tender cake.
Good to Know
Store covered at room temperature for up to 3 days or refrigerated for up to 1 week.
Cake can be baked 1 day ahead and frosted the day of serving. Store covered.
Serve at room temperature for best flavor and texture. Cut with sharp knife for clean slices.
Common Mistakes
Use microwave at 50% power to avoid overheating and seizing the chocolate.
Cool chocolate mixture slightly before adding eggs to prevent scrambling.
Refrigerate frosting fully before beating to achieve proper light texture.
Substitutions
Dairy-Free Swaps
Check label to ensure no milk ingredients
Use thick cream from top of chilled coconut milk can
Full guide →Gluten-Free Swaps
Works well with cup-for-cup blends
FAQ
Can I use regular cocoa powder instead of Dutch-processed?
Yes, but add 1/4 teaspoon baking soda to balance the acidity difference. The flavor will be slightly more acidic but still delicious.
What if my frosting is too thick or thin?
If too thick, let it sit at room temperature briefly. If too thin, refrigerate longer before beating, or beat in powdered sugar gradually.
How long will this cake keep?
Covered at room temperature for 3 days, or refrigerated up to 1 week. Bring to room temperature before serving for best taste.