Bar specialties syrup
Simple Syrup for Cakes (Cake Soaking Syrup)
The bakery trick for moist layer cakes: a light vanilla syrup brushed on each layer.
- 26 min total
- 1 cup + 2 tbsp270 ml
- Keeps 3 weeks
Photo: Keith Jay · CC BY-SA 4.0
Quick answer
Simple syrup for cakes is a 1:1 sugar syrup, flavored with vanilla, brushed onto cooled cake layers to keep them moist. Use about 2–3 tbsp per 8-inch layer (3–4 tbsp for 9-inch), and let it soak in before frosting.
Professional bakers brush syrup onto layers because it keeps cakes moist for days, protects them in the fridge and freezer, and adds a layer of flavor. It won't make a cake soggy if you measure it.
This batch makes just over a cup, enough for two 3-layer 8-inch cakes. Flavor it to match the frosting: vanilla is the default, with lemon, coffee and liqueur versions below.
Tastesvanillalight sweetness
The recipe
Simple Syrup for Cakes (Cake Soaking Syrup)
Ingredients for 1 cup + 2 tbsp270 ml
You’ll need: small saucepan, pastry brush, cake turntable, squeeze bottle, measuring cups, vanilla extractsmall saucepan, pastry brush, cake turntable, squeeze bottle, measuring cups, vanilla extract
Method
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Make the syrup
Combine the sugar, water and citrus peel (if using) in a small saucepan. Heat, stirring, until the sugar dissolves, then simmer for 1 minute.
¾ cup150 g granulated sugar¾ cup180 ml water1 strip of lemon or orange peel
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Cool
Take off the heat and let it cool to room temperature, about 20 minutes. The peel keeps infusing as it cools.
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Flavor
Remove the peel and stir in the vanilla, salt and liqueur. Adding them to cooled syrup keeps the flavor bright.
1 tsp1 tsp pure vanilla extract
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Brush the layers
Level cooled or chilled cake layers. Brush 2–3 tbsp (30–45 ml) evenly over the cut surface of each 8-inch layer, working from the edges toward the center.
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Let it soak in
Wait 5 minutes for the syrup to absorb before filling, stacking and frosting.
Storage. Keeps about 3 weeks sealed in the fridge; lemon-juice versions about 1 week. Discard if cloudy or sour-smelling. Syrup-brushed cake layers freeze well, wrapped airtight, for up to 1 month.
Per 1 tbsp (15 ml): about 33 kcal, 8.5 g sugar (estimate).
How to use it
Layer cakes
2–3 tbsp (30–45 ml) per 8-inch layer, 3–4 tbsp (45–60 ml) per 9-inch layer, brushed on before the crumb coat.
Sponge & genoise
Up to ¼ cup (60 ml) per layer. These drier cakes are designed to be soaked.
Make-ahead & tiered cakes
Brush layers before wrapping and freezing; the syrup keeps them moist through freezing, thawing and refrigeration.
Cupcakes
1–2 tsp (5–10 ml) brushed over each cupcake top before frosting.
Bundt & rum cakes
The exception to the cool-on-cool rule: poke the warm cake all over and spoon warm syrup over it so it soaks deep.
Gear for this recipe
Ateco Revolving Cake Decorating Stand
Spin the cake as you brush on soaking syrup and frost, for even moisture edge to edge. A heavy base keeps it steady.
Best for Layer cakes and soaking syrups
OXO Good Grips Chef's Squeeze Bottles (12 oz + 16 oz)
Best for Sauces, drizzles and latte art
OXO Good Grips Silicone Pastry Brush
Best for Soaking cake layers
Nielsen-Massey Madagascar Bourbon Vanilla Bean Paste (4 oz)
Best for Vanilla bean flavor without pods
More gear for this recipe (3)
Nielsen-Massey Madagascar Bourbon Pure Vanilla Extract (4 oz)
Best for Vanilla, caramel and chocolate syrups
Cuisinart Chef's Classic 1.5 qt Stainless Saucepan with Lid
Best for Every stovetop syrup
Pyrex 3-Piece Glass Measuring Cup Set (1, 2 & 4 cup)
Best for Measuring, microwaving and pouring
Tips for the best batch
- Cool syrup on cool cake. Brushing chilled or room-temperature layers gives even absorption and they won't tear. Warm syrup on warm cake can turn it gummy.
- Measure it out. Pour each layer's share into a small cup so you can't overdo it. Puddles on the surface mean too much.
- Sponge, genoise and chiffon cakes are made to drink syrup and can take ¼ cup (60 ml) per layer. Rich butter cakes need less.
- For cupcakes, brush or poke and spoon 1–2 tsp over each top before frosting.
- A squeeze bottle or clean spray bottle gives very even coverage on large or tiered cakes.
Variations
Lemon soak
Replace 60 ml of the water with fresh lemon juice and add the zest of 1 lemon. Good for lemon and blueberry cakes; use within 1 week.
Coffee soak
Dissolve the sugar in 180 ml hot strong coffee or espresso instead of water. Use on chocolate cake or tiramisu-style layers.
Boozy soak
Increase the liqueur to 30–45 ml: rum for banana or coconut cake, orange liqueur for chocolate, amaretto for almond.
Light syrup
Use 100 g sugar to 180 ml water if your frosting is already very sweet.
Questions people ask
Why do bakers put simple syrup on cakes?
It keeps layers moist for days, protects them from drying out in the fridge or freezer, and adds flavor. Bakeries use it especially on cakes made ahead.
How much simple syrup should I use per cake layer?
About 2–3 tbsp (30–45 ml) for an 8-inch layer and 3–4 tbsp (45–60 ml) for a 9-inch layer. Sponge and genoise cakes can take up to ¼ cup (60 ml).
Should the cake be warm or cold when I add syrup?
Cooled or chilled is best for layer cakes: the syrup absorbs evenly and the layers don't tear. Bundt and rum cakes are the exception: warm syrup on warm cake.
Will simple syrup make my cake soggy?
Not if you measure. Brush on the recommended amount and let it soak in for a few minutes. If it pools on the surface, you've added too much.
Can I brush simple syrup on cupcakes?
Yes. Brush or spoon 1–2 tsp over each cupcake before frosting. It's a great fix for a batch that baked a little dry.