Deep Sea Cake Recipe
If you’re searching for the most whimsical, magical dessert to delight both kids and grown-ups, you’ve officially found it—Deep Sea Cake is a true showstopper. This layered vanilla cake is transformed into a vibrant ocean fantasy, rippling with ombré blues and dotted with edible seashells, pearls, and shimmering “sand.” It’s the ultimate centerpiece for any celebration where fun and flavor are equally important, and each bite is as enchanting as it looks.

Ingredients You’ll Need
The best part about making Deep Sea Cake is that it uses straightforward ingredients—each one is essential for creating incredible flavor, tender texture, and those ocean-inspired colors that make this cake pop. Here’s what you’ll need and why you shouldn’t skip a thing:
- All-purpose flour: The backbone of your cake, lending sturdiness and softness in each layer.
- Baking powder: Gives those beautiful layers their lift and fluffiness.
- Salt: A pinch is all it takes to enhance every sweet note.
- Unsalted butter (room temp): Essential for a rich, tender crumb and dreamy buttercream.
- Granulated sugar: Sweetens the cake while helping to create a light, airy texture.
- Eggs (room temp): Bind everything together and add structure and richness to each bite.
- Vanilla extract: Deepens the flavor with cozy, classic notes that never go out of style.
- Whole milk (room temp): Keeps the cake moist and helps everything blend perfectly.
- Blue gel food coloring: Use varying shades to create those signature under-the-sea ombré layers.
- Powdered sugar: Makes for super-smooth, fluffy buttercream with just the right sweetness.
- Heavy cream or milk: Adds silkiness and helps lighten the buttercream to just the right consistency.
- Edible seashells & starfish: Molded from white chocolate or candy melts, these bring the sea to your cake!
- Coral decorations: Crafted from piped, hardened white chocolate to add playful texture.
- Crushed graham crackers: Sprinkled as “sand” for a realistic and tasty touch.
- Pearl (white chocolate truffle): Tuck this inside a fondant shell as the crowning jewel.
- Pearl shell (fondant or sugar paste): Mold by hand for an ocean treasure effect.
- Edible shimmer dust or luster spray (optional): Mist for that spellbinding, oceanic sparkle.
How to Make Deep Sea Cake
Step 1: Prepare and Bake the Cake Layers
Let the fun begin! Set your oven to 350°F (175°C), and give three 8-inch round pans a generous greasing and line the bottoms with parchment for easy removal. Whisk together the flour, baking powder, and salt. In a separate bowl, beat your softened butter and sugar until the mixture looks pale and fluffy—this step sets the stage for a light cake. One at a time, add the eggs, then swirl in vanilla. Alternate adding dry ingredients and milk, mixing just until blended. Divide the batter evenly into three bowls and tint each a different oceanic blue—get creative! Pour into the pans and bake for 25–30 minutes, until a toothpick comes out clean. Let the layers cool completely.
Step 2: Whip Up the Dreamiest Buttercream
A silky buttercream makes Deep Sea Cake unforgettable. Begin by beating your butter until it’s smooth and luxurious. Add powdered sugar slowly to avoid a sugar cloud, then vanish any lumps by blending in vanilla and just enough cream or milk to achieve a fluffy, spreadable texture. Divide the frosting into a few bowls and tint with various blue shades, from pale to navy. Start with a thin crumb coat on your cooled cake (this locks in crumbs!), chill, and then layer on your ombré or wave-like buttercream from light to dark. An offset spatula or palette knife makes painting on those whimsical waves a joy.
Step 3: Decorate with Undersea Magic
Here’s where Deep Sea Cake comes to life! Use silicone molds to create chocolate seashells and starfish, dusting them with shimmer for that just-came-from-the-ocean glow. Pipe melted white chocolate onto parchment in wiggly coral shapes and let them harden. At the cake’s base, sprinkle a sandy layer of crushed graham crackers, and for the ultimate ocean treasure moment, nestle a white chocolate pearl inside a hand-molded fondant clamshell right on top. Finish with a gentle mist of edible shimmer spray for that water-inspired sparkle everyone loves.
How to Serve Deep Sea Cake

Garnishes
A sprinkle of shimmer, a handful of edible pearls, or a drift of extra graham cracker “sand” turns every slice into a celebration of the sea. If you want your Deep Sea Cake to really shine, don’t hold back on placing seashells, coral, and starfish all around the base and top—this is your chance to go overboard in the best possible way!
Side Dishes
Keep it simple so Deep Sea Cake can take center stage. A big bowl of fresh mixed berries or a scoop of light vanilla bean ice cream pairs perfectly and lets those ocean-inspired flavors pop. For a more festive party, sparkling lemonade or a tropical fruit punch is absolutely delightful alongside each dreamy blue slice.
Creative Ways to Present
Don’t be afraid to let your imagination swim wild! Try serving Deep Sea Cake on a cake stand wrapped with shells and faux pearls, or use mini individual cakes for a charming under-the-sea dessert display. For a magical birthday, surround the cake with blue glass pebbles and toy sea creatures, or tuck sparkly candles among the shells for a true mermaid’s treasure.
Make Ahead and Storage
Storing Leftovers
Deep Sea Cake is just as delicious the next day. Cover leftover slices well with plastic wrap or store in an airtight container in the refrigerator for up to 3–4 days. The buttercream keeps the cake moist and tasty, so no one will feel like they’re just eating leftovers!
Freezing
To freeze, wrap individual cake layers (unfrosted) tightly in plastic and foil, then pop them in the freezer for up to two months. Buttercream can be stored in an airtight container and frozen separately. Decorations like seashells or pearls should be stored at room temperature until ready to assemble.
Reheating
There’s really no need to reheat Deep Sea Cake—simply let slices come back to room temperature before serving for the best texture and flavor. If you’ve frozen your layers or cake, give them plenty of time to fully thaw before decorating or eating.
FAQs
Can I use cake flour instead of all-purpose flour?
Absolutely! Cake flour will make the layers even more delicate and soft. Swap in the same weight (not just the volume) for the all-purpose flour if you want a super-tender crumb.
What if I don’t have gel food coloring?
Gel is recommended because it delivers bold colors without watering down the batter or frosting, but you can use liquid food coloring in a pinch—just use it sparingly to avoid thinning out your mixtures.
Can I make Deep Sea Cake gluten-free?
Yes! Substitute your favorite 1:1 gluten-free flour blend for the regular flour. Double-check that your decorations (like candy melts) are also gluten-free to keep things safe for everyone.
How far in advance can I decorate the cake?
It’s best to decorate Deep Sea Cake within 24 hours of serving it for the freshest look. However, the cake and buttercream can be made up to two days ahead; just store separately and assemble when you’re ready for maximum wow-factor.
Can I use different colors for a different theme?
Absolutely! While blues are iconic for Deep Sea Cake, you can swap in pastels for a coral reef vibe or even sunset shades for an “underwater at dusk” look. Have fun and let your creativity shine!
Final Thoughts
There’s something about Deep Sea Cake that turns any day into a special occasion—the ombré blues, playful decorations, and cloud-soft vanilla cake all combine for pure magic. If you’ve never made a cake like this before, don’t worry; half the fun is letting your creativity run wild. Gather your friends and loved ones, and dive into your own delicious ocean adventure!
PrintDeep Sea Cake Recipe
This Deep Sea Cake is a stunning ocean-inspired dessert that will impress your guests with its intricate decorations and delicious flavors. The vanilla cake layers are tinted in varying shades of blue and frosted with ombré buttercream, adorned with edible seashells, coral, and pearls for a true under-the-sea experience.
- Prep Time: 45 minutes
- Cook Time: 30 minutes
- Total Time: 1 hour 15 minutes
- Yield: 1 3-layer 8-inch cake 1x
- Category: Dessert
- Method: Baking
- Cuisine: American
- Diet: Vegetarian
Ingredients
For the Vanilla Cake (3 layers – 8-inch pans)
- 2 ½ cups (315g) all-purpose flour
- 2 ½ tsp baking powder
- ½ tsp salt
- 1 cup (226g) unsalted butter, room temp
- 2 cups (400g) granulated sugar
- 4 large eggs, room temp
- 1 tbsp vanilla extract
- 1 cup (240ml) whole milk, room temp
- Blue gel food coloring (varying shades)
For the Buttercream
- 1 ½ cups (340g) unsalted butter, room temp
- 5 cups (600g) powdered sugar
- 2–4 tbsp heavy cream or milk
- 1 tbsp vanilla extract
- Blue gel food coloring (light blue, medium blue, navy)
Decorations
- Edible seashells, starfish (molds with candy melts or white chocolate)
- Coral (melted white chocolate piped into coral shapes and hardened)
- Crushed graham crackers (for “sand”)
- Pearl: A white chocolate truffle or hand-molded sugar pearl
- Pearl shell: Made from fondant or sugar paste
- Edible shimmer dust or luster spray (optional)
Instructions
- Make the Cake Layers – Preheat oven to 350°F (175°C). Grease and line 3 8-inch round pans. In a bowl, whisk flour, baking powder, and salt. In another bowl, cream butter and sugar until fluffy. Add eggs one at a time, then vanilla. Add flour mixture in 3 parts, alternating with milk. Divide batter into 3 bowls. Tint each a different shade of blue. Pour each into a prepared pan and bake 25–30 mins. Cool completely.
- Buttercream Frosting – Beat butter until creamy. Slowly add powdered sugar. Add vanilla and cream until fluffy. Divide and tint in multiple blue shades. Apply a crumb coat, chill for 30 mins. Apply ombré or wave-like layers of buttercream (light to dark).
- Decorate – Shells & Starfish: Use silicone molds and white chocolate or candy melts. Dust with edible gold or pearl shimmer. Coral: Pipe melted white chocolate onto parchment in coral shapes, let harden. Sand: Sprinkle crushed graham crackers at the base. Pearl & Shell: Form an open clamshell with fondant/sugar paste. Place a truffle or candy pearl inside.
Notes
- Use an offset spatula or palette knife for wave-like frosting textures.
- Freeze cake layers for 30 mins before stacking to reduce crumbs.
- For extra elegance, add a light mist of edible pearl spray for shimmer.
Nutrition
- Serving Size: 1 slice (1/12 of cake)
- Calories: 480
- Sugar: 45g
- Sodium: 280mg
- Fat: 24g
- Saturated Fat: 15g
- Unsaturated Fat: 7g
- Trans Fat: 0g
- Carbohydrates: 62g
- Fiber: 1g
- Protein: 4g
- Cholesterol: 100mg
Keywords: Deep Sea Cake, Ocean Cake, Under the Sea Cake, Blue Cake, Vanilla Cake