Ingredients
Method
Prepare the pans
- Preheat your oven to 320°F (160°C).
- Line the bottoms of two 6-inch cake pans with parchment paper.
- I prefer baking this sponge at a lower temperature. It gives the center time to bake through while helping the cake rise more evenly without overly dry or dark edges.
Whip the eggs properly
- Add the eggs, sugar, and salt to a large mixing bowl.
- Beat with a mixer for 7–10 minutes, until the mixture becomes very pale, thick, fluffy, and several times larger in volume.
- Don’t judge only by time — look at the texture.
- Lift the whisk and let some of the mixture fall back into the bowl. It should fall in a thick ribbon and remain visible on the surface for a few seconds.
- This is one of the most important steps in the entire recipe.
- If the eggs aren’t whipped enough, your sponge can turn out short and dense.
Add the oil
- Add the oil and vanilla extract.
- Mix on low speed just until combined.
- Once your eggs are beautifully whipped, you don’t want to beat the mixture unnecessarily and lose the air you created.
Prepare the milk mixture
- In a separate bowl, combine the milk and sour cream.
- They should be approximately room temperature rather than very cold.
- If they’re straight from the refrigerator, microwave the mixture for about 10–15 seconds.
- It should not be hot.
Add the dry ingredients
- Sift the flour and baking powder together.
- Add the flour mixture to the whipped eggs alternately with the milk and sour cream mixture.
- Mix gently and only as much as necessary.
- Use a spatula to scrape the bottom of the bowl. Sometimes flour or heavier liquid can hide underneath even when the batter looks completely mixed on top.
- Your finished batter should still look fluffy and airy.
Bake
- Divide the batter evenly between the prepared pans.
- Bake at 320°F (160°C) for approximately 40–45 minutes.
- Try not to open the oven during the first part of baking.
- Check the center with a toothpick. It should come out clean or with a few dry crumbs.
- The center should also gently spring back when lightly touched.
Cool before slicing
- Let the sponge cool in the pan for about 30–40 minutes, then transfer it to a cooling rack.
- Cool completely.
- Wrap the sponge tightly in plastic wrap and refrigerate for 2–4 hours before slicing.
- A rested, chilled sponge is much easier to cut into thin, even cake layers without tearing or crumbling.
Notes
Why Does My Sponge Cake Sink?
A sponge that looks beautiful in the oven and collapses afterward usually has a problem with structure, temperature, or baking time. Here are the first things I would check:1. The center is underbaked
- This is one of the most common reasons.
- The outside can look completely finished while the center still doesn’t have enough structure to support the cake.
- Always check the very center before removing the sponge from the oven.
2. You opened the oven too early
- Opening the oven causes a sudden temperature change.
- Wait until the cake has risen and is close to fully baked before opening the door.
3. The eggs weren’t whipped enough
- Your eggs should become extremely pale, thick, and fluffy.
- If they’re still thin and runny, keep whipping.
4. You overmixed the batter
- Once the eggs are whipped, treat that volume carefully.
- Aggressive mixing after adding the flour and liquids can knock out the air and leave you with a dense or collapsed sponge.
5. Too much baking powder
- More baking powder does not mean a taller cake.
- Too much can make a cake rise too quickly before its structure is strong enough, which can contribute to collapsing.
- Measure it carefully.
6. Your oven is too hot
- If your sponge rises very quickly, becomes dark around the edges, but remains wet in the center, your oven may be running hotter than the temperature shown.
- If you bake often, an inexpensive oven thermometer is worth having.
Why Is My Sponge Cake Dense?
If the cake isn’t as fluffy as expected, check these first:- Eggs weren’t whipped long enough.
- Too much flour was added.
- Flour was packed into the measuring cup.
- Batter was overmixed.
- Too much air was lost while adding the flour and liquids.
- Baking powder was old.
- Ingredients were measured incorrectly.
Why Is My Sponge Cake Dry?
Usually it’s one of three things:- Too much flour, too much heat, or too much baking time.
- This recipe also uses two ingredients that help prevent dryness:
- Oil keeps the sponge soft, especially after refrigeration.
- Sour cream gives the crumb extra moisture and tenderness.
- For layered cakes, I also like to lightly soak the sponge.
How to Soak Sponge Cake
- A light soak can take a good sponge cake to another level.
- It adds moisture and lets you change the flavor of the cake without changing the basic sponge recipe.
- For my basic simple soak, combine:
- 1 cup water + 2 tsp sugar
- You can also simply use milk.
- Brush or drizzle a small amount over each cut cake layer.
- The goal is a beautifully moist cake — not a wet cake.
- Start with less. You can always add more.
Easy Sponge Cake Soak Ideas
- Vanilla Milk:
Milk + vanilla extract. Simple and perfect for berry cakes. - Lemon:
Water + sugar + fresh lemon juice and lemon zest.- Perfect with raspberries, blueberries, strawberries, or lemon cream.
- Orange:
Simple syrup + fresh orange zest and a little orange juice. - Berry:
Add strained raspberry or strawberry juice to your syrup. - Coffee:
Coffee + a little sugar.- Perfect with chocolate, caramel, mascarpone, or dulce de leche fillings.
- Coconut:
Use a light coconut milk soak with mango, pineapple, passion fruit, or coconut fillings.
Easy Ways to Change the Sponge Flavor
Once you have a reliable vanilla sponge, you can use it as the base for many different cakes.Lemon
- Add finely grated lemon zest to the batter.
- You can also use lemon syrup between the layers.
Orange
Add fresh orange zest and pair it with an orange-flavored soak.Almond Vanilla
- Add a small amount of almond extract together with the vanilla.
- It’s especially good with cherries, raspberries, or strawberries.
Coffee
- Dissolve instant espresso powder into the milk before adding it to the batter.
- Pair it with mascarpone, chocolate, caramel, or dulce de leche.
Coconut
Add a little coconut extract and pair the sponge with mango, pineapple, or passion fruit.Chocolate
- Chocolate requires a little more care.
- Don’t simply add cocoa powder to the original recipe. Cocoa absorbs moisture and changes the balance of the batter.
- For a chocolate version, part of the flour should be replaced with cocoa powder rather than simply adding cocoa to the existing amount of flour.
Ingredients That Make a Difference
Eggs
- Eggs provide structure and much of the air that makes this sponge fluffy.
- Use the egg size specified in the recipe and whip them properly.
Flour
- Too much flour makes sponge cake dense and dry.
- A kitchen scale gives the most consistent results.
Sugar
- Sugar doesn’t only make cake sweet. It also affects moisture, texture, and the stability of the whipped egg mixture.
- Don’t dramatically reduce it and expect exactly the same result.
Baking Powder
- Use fresh baking powder and measure accurately.
- Extra baking powder isn’t a shortcut to a taller sponge.
Oil
- Oil helps the sponge stay soft and moist, including after refrigeration.
- Choose a neutral, odorless oil so it doesn’t compete with the vanilla flavor.
Sour Cream
Sour cream is one of my favorite parts of this recipe. It gives the sponge a softer, more tender crumb while helping it stay moist.Milk
- Milk adds moisture and helps create the soft texture.
- For best results, don’t add it ice-cold to your whipped egg mixture.
My Most Important Sponge Cake Tips
- Weigh your ingredients whenever possible.
- Bring eggs and dairy closer to room temperature.
- Whip eggs and sugar for 7–10 minutes until thick and fluffy.
- Sift flour and baking powder.
- Don’t overmix after adding flour.
- Scrape the bottom of the bowl before filling the pans.
- Bake at 320°F (160°C).
- Don’t open the oven too early.
- Make sure the center is completely baked.
- Cool completely before wrapping.
- Refrigerate for 2–4 hours before slicing.
- Lightly soak the layers for an extra-moist finished cake.