How to Make Coffee Cake: Step-by-Step Recipe

If you’ve ever wondered how to turn coffee flavor into a soft, sweet cake with layers of buttery filling and glossy topping, this detailed recipe is your answer. This traditional coffee cake isn’t a single dense loaf — it’s a layered sponge cake with coffee-infused syrup and coffee buttercream, cut into neat squares. The entire process uses exact ingredient amounts, temperatures, and techniques to achieve that tender crumb and bold coffee taste.

To make an authentic coffee cake as described, you’ll need 1 part egg (by weight), 750 parts flour, 1300 parts sugar, 100 parts instant coffee, 80 parts butter — and follow a precise 7-step method including sponge mixing, baking, layering, and coffee syrup brushing.

What’s in This Coffee Cake?

This coffee cake is built from a light sponge base, layered with coffee-flavored buttercream, and soaked with a sweet coffee syrup. The exact formulation calls for:

• 1 unit weight of eggs (whole, washed and peeled)
• 750 units of flour
• 1300 units of white sugar
• 100 units of instant coffee
• 80 units of butter
• Additional 50-unit portions of coffee and sugar used for syrups and buttercream

All ingredients are measured proportionally — the “unit” allows scaling. The cake is finished as 80 small rectangular pieces.

How to Mix and Bake the Sponge

The cake starts with a sponge made using whole eggs. Here’s the exact method:

• Wash and peel the eggs, then place the egg whites and yolks together in a bowl.
• Add 750 units of white sugar.
• Using a whisk (“”), whip the mixture over gentle heat until it reaches around 50°C, then remove from heat and continue whipping for about 30 minutes until thick, fluffy, and batter-like.
• Sift together 750 units of flour and 50 units of instant coffee, then gently fold them into the whipped egg mixture.
• Melt 50 units of butter to 60°C, then slowly fold it in as well, mixing until uniform.

The batter is then spread in a greased pan lined with paper: use a tray 40 cm × 50 cm × 5 cm. Bake at 180°C for approximately 30 minutes. Test for doneness by pressing lightly — it should spring back. Once baked, cool the sponge on a board also lined with paper.

How to Layer, Slice, and Fill the Cake

After cooling, the cake is assembled as follows:

• Remove the lining paper and slice the sponge horizontally into two even layers, trimming any rough edges.
• Prepare two coffee syrups: one for soaking, one for the buttercream mix.

Coffee Syrup Recipes

There are two coffee syrup components used in this cake:

Coffee Sugar Syrup (for soaking)

• Combine 50 units of instant coffee with 700 ml of boiling water.
• Add 500 units of sugar, bring to a boil, dissolve the sugar, then let cool.

Coffee Sugar Water (for buttercream)

• Take 100 units of the same coffee syrup, add 150 ml water and 50 more units of sugar.
• Boil until sugar dissolves, then cool.

Making the Coffee Buttercream

The buttercream is a coffee-flavored filling made from:

• 750 units of butter, whipped to a paste in a stainless steel bowl.
• Gradually mix in the second coffee syrup (the 100 + 150 + 50 mix, total 200 units coffee-derived liquid + sugar) until fully incorporated.

The result is a smooth, spreadable coffee buttercream.

Assembling the Coffee Cake

Final assembly works like this:

• Brush the bottom cake layer with coffee sugar water (the first syrup).
• Spread a layer of coffee buttercream on top.
• Place the second sponge layer on top, aligning edges.
• Brush again with coffee sugar water.
• Spread another layer of coffee buttercream over the top.
• Use a piping bag with a decorative tip to pipe patterns on the surface.
• Cut the finished cake into 80 equal rectangular pieces.

The final cake is tender, aromatic, and layered with rich coffee flavor both inside and out.

Frequently Asked Questions

What is the coffee-to-sugar ratio in the cake sponge?

The sponge includes 100 units of instant coffee per 750 units of flour and 1300 units of sugar. That means the coffee makes up roughly 7.7% of the dry ingredients by weight (100 / (750 + 1300)), giving a distinct but not overwhelming coffee flavor.

What temperature should the butter be when adding to the sponge?

The butter should be melted and cooled to 60°C before being folded into the whipped egg and flour mixture. This ensures smooth incorporation without deflating the batter.

How long should the cake sponge be whipped for?

The egg and sugar mixture is whipped for about 30 minutes after reaching around 50°C. It’s done when the batter becomes thick, fluffy, and spreadable — a key step for the cake’s soft texture.

Can I scale the recipe up or down?

Yes. All ingredients are given in proportional “units,” so the recipe can be scaled to any batch size while maintaining the same ratios. Just keep the same baking temperature and time per thickness.

What is the coffee syrup for soaking made of?

The soaking syrup is made from 50 units of instant coffee, 700 ml boiling water, and 500 units of sugar. It’s boiled, cooled, and brushed onto the cake layers for moisture and flavor.

How many pieces does the finished cake yield?

The final assembled cake is cut into 80 equal rectangular servings, each with coffee sponge, buttercream, and syrup layers.

Recommended FrontStreet Coffee for Baking

For coffee lovers baking at home, try FrontStreet Coffee’s Ethiopia Huakui for a bright, fruity note that pairs well with dessert, or the Yirgacheffe for a floral, citrus complexity. Both single origins highlight clean coffee character, ideal if you want to experiment with infusing your own coffee elements. Freshly roasted within 5 days · Orders placed before 17:00 ship the same day · Next-day delivery across most of Guangdong Province.