Tres Leche Cake: Sourdough

If you’ve ever had tres leches cake, you know it’s one of the dreamiest desserts out there—ultra moist, rich, and soaked with sweet milks. Now imagine that same beloved Latin American classic, but with the deep flavor and tender crumb that only sourdough can give you. That’s right—Sourdough Tres Leches Cake is here to change the way you do dessert.

Whether you’re looking to use up some sourdough discard, impress your friends at a dinner party, or just want a new go-to cake recipe, this is the ultimate indulgence. In this post, I’ll walk you through every step of the process, from baking the cake to soaking it in the signature three-milk blend, topping it with whipped cream, and even storing leftovers.

This recipe is beginner-friendly, perfect for spring and summer parties, and a great way to get creative with your sourdough starter. Ready to dive in?

What is Tres Leches Cake?

Tres leches means “three milks” in Spanish, and that’s exactly what this cake is soaked in—a mixture of sweetened condensed milk, evaporated milk, and whole milk or cream. The result is a super moist cake that’s not soggy, but wonderfully saturated. Traditionally, it’s made with a light sponge cake so it can absorb all that milk without falling apart.

Adding sourdough to the mix gives the cake a tangy depth of flavor that pairs beautifully with the sweet creaminess of the milk mixture.

Why You’ll Love This Sourdough Version

• Great use for discard: This recipe uses sourdough discard, so nothing goes to waste.

• Make-ahead friendly: This cake is better when made a day in advance.

• Light yet rich: Despite being soaked in milk, the sponge is airy and light, not dense.

• Perfect for special occasions: Birthdays, Mother’s Day, Cinco de Mayo, baby showers—you name it.

Ingredients You’ll Need

For the Cake:

• 1 cup all-purpose flour

• 1 ½ tsp baking powder

• ¼ tsp salt

• 5 large eggs, separated

• 1 cup granulated sugar, divided

• ½ cup sourdough discard (unfed is fine)

• ⅓ cup whole milk

• 1 tsp vanilla extract

For the Milk Soak:

• 1 (14 oz) can sweetened condensed milk

• 1 (12 oz) can evaporated milk

• 1 cup heavy cream or whole milk

For the Whipped Cream Topping:

• 2 cups heavy whipping cream

• 3 tbsp powdered sugar

• 1 tsp vanilla extract

Optional Toppings:

• Fresh berries

• Cinnamon

• Toasted coconut

• Maraschino cherries

Tools You’ll Need

• Stand or hand mixer

• Mixing bowls

• 9x13 inch baking dish

• Sifter or fine mesh strainer

• Whisk

• Rubber spatula

Sourdough Tres Leches Cake

Step 1: Make the Sponge Cake

1. Preheat your oven to 350°F (175°C). Grease a 9x13-inch pan and set aside.

2. Sift together the dry ingredients: flour, baking powder, and salt.

3. In a large mixing bowl, beat the egg yolks with ¾ cup sugar until pale and fluffy (about 3 minutes). Add vanilla, milk, and sourdough discard. Mix until smooth.

4. Gently fold in the flour mixture until fully incorporated.

5. In a separate clean bowl, whip the egg whites until soft peaks form. Gradually add the remaining ¼ cup of sugar and continue beating until stiff peaks form.

6. Fold the whipped egg whites into the batter in thirds, being careful not to deflate the mixture. The batter should be light and airy.

7. Pour into the prepared pan and spread evenly.

8. Bake for 25–30 minutes, or until a toothpick inserted in the center comes out clean.

9. Let the cake cool completely in the pan.

Step 2: Prepare the Tres Leches Mixture

In a large bowl or measuring cup, combine:

• 1 can sweetened condensed milk

• 1 can evaporated milk

• 1 cup heavy cream or whole milk

Whisk until smooth. Once the cake is fully cooled, poke holes all over it using a fork or skewer. Go deep, but not all the way to the bottom.

Slowly pour the milk mixture over the cake, letting it soak in as you go. Be patient—it might take a couple of rounds of pouring to get it all in.

Cover and refrigerate the cake for at least 4 hours, preferably overnight. This step is crucial!

Step 3: Make the Whipped Cream Topping

Right before serving (or a few hours ahead), make the topping:

1. In a chilled mixing bowl, beat the heavy cream until soft peaks form.

2. Add powdered sugar and vanilla, then continue to beat until stiff peaks form.

3. Spread over the soaked cake and garnish with toppings of your choice.

Tips for Success

• Don’t skip the resting time. The cake needs hours to absorb all that milky goodness.

• Use cold whipping cream for the fluffiest topping.

• You can freeze the sponge cake (before soaking) if prepping ahead.

• For a boozy twist, add 1–2 tbsp of rum or brandy to the milk mixture.

Storage and Make-Ahead Tips

• This cake keeps well in the fridge for 3–4 days.

• Store it covered with plastic wrap or in an airtight container.

• The whipped topping may need refreshing after a few days—just whip a bit more cream and reapply!

Sourdough Discard FAQ

Can I use active starter instead of discard?
Yes! If you don’t have discard, an active starter will work just fine. The cake might be a little more airy.

Will it taste sour?
Nope! The milk mixture balances everything out. You’ll get a subtle tang, but nothing overpowering.

Can I make this gluten-free?
Try substituting the flour with a good 1:1 gluten-free baking flour, but results may vary slightly.

Variations to Try

• Coconut Tres Leches: Swap out some of the milk for coconut milk and top with toasted coconut flakes.

• Chocolate Tres Leches: Add ¼ cup cocoa powder to the flour and substitute some milk for chocolate milk in the soak.

• Berry Tres Leches: Layer in sliced strawberries or blueberries between the whipped cream and cake.

Perfect for Any Occasion

This Sourdough Tres Leches Cake is versatile, stunning, and most importantly—delicious. It’s the perfect showstopper dessert for:

• Cinco de Mayo

• Baby showers

• Summer BBQs

• Mother’s Day brunch

• Birthday celebrations

Serve it straight from the pan with fresh fruit or a sprinkle of cinnamon for an extra touch of love.