Costco Tres Leches Cake Recipe: Soaked in Creamy Three-Milk Bliss

This tres leches cake delivers the same creamy indulgence you’d find at Costco, without the bakery price tag. I recreated their version after one too many trips for “just a slice” turned into full cakes in my cart.

The secret is soaking a light vanilla sponge in a blend of evaporated milk, sweetened condensed milk, and heavy cream. Every bite stays moist and rich, with whipped topping adding the final touch.

Unlike box mixes, this homemade version lets you control the sweetness and texture. The cake bakes in 30 minutes, then soaks up the milk mixture while cooling.

Perfect for birthdays, potlucks, or when you need a dessert that feels like a treat. Here’s how to make it.

Ingredients for Costco Tres Leches Cake

A light vanilla sponge plus three kinds of milk. Costco-level indulgence at home.

The evaporated and sweetened condensed milk are non-negotiable for that signature tres leches soak. Carnation and Nestlé are reliable brands at any grocery store. For the heavy cream, Whole Foods 365 or Organic Valley have great options. The butter should be unsalted so you control the salt level—Land O’Lakes is my go-to. Fresh eggs at room temp whip up lighter, so pull them out an hour before baking.

No evaporated milk? Simmer regular milk until reduced by half—works in a pinch. Out of sweetened condensed? Make your own with powdered sugar and milk (1:1 ratio, simmered). The whipped topping can be Cool Whip (thawed) or homemade whipped cream if you’re feeling fancy. Cake flour works too, but all-purpose with baking powder gives a similar crumb for less fuss.

Baked cake keeps covered at room temp for 2 days, but it’s best the same day. Once soaked, refrigerate up to 5 days—the flavors just get better. Freeze slices for up to 3 months (thaw in the fridge overnight).

Step-by-Step Instructions for Tres Leches Cake

Here’s the method. Simple steps, incredible results every time.

Step 1: Prepare and Bake the Sponge Cake

Preheat your oven to 350°F and grease a 9×13-inch baking dish. In a large bowl, whisk together the 2 cups All-Purpose Flour, 1.5 tsp Baking Powder, and 0.25 tsp Salt until well combined. Sifting the flour first gives you that light, airy texture you want.

In a separate bowl, beat the 5 whole Large Eggs with 1.5 cups Granulated Sugar until pale and thick, about 3-4 minutes. Slowly incorporate the melted 0.5 cup Unsalted Butter and 2 tsp Vanilla Extract, then alternate adding the flour mixture and 0.25 cup Whole Milk until just combined. Pour into your prepared pan and bake for 25-30 minutes until a toothpick inserted in the center comes out clean.

Step 2: Prepare the Three-Milk Soaking Liquid

While the cake bakes, combine the 12 oz Evaporated Milk, 14 oz Sweetened Condensed Milk, and 1 cup Heavy Cream in a large measuring cup or bowl. Whisk until fully blended—this creates that rich, creamy soaking liquid that makes this cake legendary.

I like to warm this mixture slightly in the microwave for 30-45 seconds before using. Warm liquid absorbs more evenly into the cake, ensuring every bite is perfectly moist without being soggy. Don’t skip this step—it makes a noticeable difference in the final texture.

Step 3: Soak the Cake Thoroughly

As soon as the cake comes out of the oven, use a skewer or fork to poke holes all over the surface. The holes don’t need to be deep—just enough to help the liquid penetrate. Slowly pour the three-milk mixture evenly over the entire cake, giving it time to absorb.

You’ll see the liquid disappear into the cake almost immediately. Let it sit at room temperature for 15-20 minutes to fully absorb. The cake should look saturated but not swimming in liquid. This is when the magic happens—the cake transforms from a simple sponge into that ultra-moist, creamy delight we all love.

Step 4: Add the Final Touches

Once the cake has absorbed all the liquid and cooled slightly, spread the 2 cups Whipped Topping evenly over the top. I prefer to use the back of a spoon to create little swirls and peaks—it looks beautiful and gives each slice a professional finish.

For the final touch, dust lightly with 0.5 tsp Ground Cinnamon. The cinnamon adds a warm, aromatic note that complements the sweetness perfectly. Chill the cake for at least 2 hours before serving to let all the flavors meld together. This waiting time is tough, but it’s absolutely worth it for that perfect texture and flavor.

Pro Cooking Tips for Perfect Results

Perfect Cake Texture

For that signature Costco lightness, don’t overmix your batter. Beat the eggs and sugar until pale but stop once the butter and milk are just incorporated. Overworking develops gluten, which makes the cake dense instead of tender. 💡

Even Soaking Secret

Warm your three-milk mixture for 30-45 seconds in the microwave before pouring. This helps it absorb more evenly throughout the cake. I learned this trick after my first attempt left dry spots near the edges.

Pro Poking Technique

Use a wooden skewer rather than a fork to poke holes. The skewer creates deeper channels without compacting the cake. Space holes about 1 inch apart across the entire surface. This ensures every bite gets soaked.

Chilling Perfection

Let the cake chill for at least 2 hours after soaking. This gives the milk mixture time to fully penetrate and the whipped topping time to set. I often make it the night before serving for maximum flavor development.

Slicing Like a Pro

Use a sharp knife dipped in hot water between cuts for clean slices. Wipe the blade clean after each cut to maintain that professional bakery look. Serve chilled but not ice-cold for the best texture.

Milk Mixture Ratio

The classic ratio is 1 part evaporated milk, 1 part sweetened condensed milk, and 1 part heavy cream. Resist the urge to add extra cream—it can make the cake too rich and heavy instead of light and creamy. ✨

Frequently Asked Questions