Chocolate Syrup (Mocha Sauce)

Before you start

This is the dark, pourable sauce that goes into a café mocha: cocoa powder simmered with sugar and water, with a little chopped dark chocolate stirred in for richness and gloss. Cocoa provides the strong chocolate flavor, while the bar chocolate adds body. Because the base is water rather than cream, it stirs easily into cold milk and keeps for weeks in the fridge.

The key step is cooking the cocoa long enough. A short simmer of 2 to 3 minutes dissolves the starch in the cocoa and gets rid of any raw, dusty taste. Use Dutch-process cocoa for a darker, smoother syrup, or natural cocoa for a fruitier, sharper one.

Ingredients

• 50 g (½ cup) unsweetened cocoa powder — Dutch-process for darkest color
• 150 g (¾ cup) granulated sugar
• 240 ml (1 cup) water
• 30 g (1 oz) dark chocolate — 60 to 70% cacao, finely chopped
• ⅛ tsp fine salt
• 1 tsp vanilla extract

Method

1. Whisk the cocoa, sugar and salt together in the saucepan to break up cocoa lumps before any liquid goes in.
2. Add about 60 ml of the water and whisk into a smooth paste, then whisk in the rest of the water.
3. Bring to a gentle boil over medium heat, whisking. Lower the heat and simmer for 2 to 3 minutes, until it is glossy and lightly coats a spoon. Keep whisking along the bottom, where cocoa can scorch.
4. Remove from the heat and add the chopped chocolate. Let it sit 1 minute, then whisk until completely melted.
5. Stir in the vanilla. Cool for about 20 minutes, then pour into a squeeze bottle or jar and refrigerate.

Tips for success

• For a mocha, stir 30 ml (1 oz) of syrup into a double shot of espresso, then add steamed milk.
• For chocolate milk, use about 2 tbsp syrup per 240 ml (8 oz) of cold milk and stir well.
• A small pinch of instant espresso powder deepens the chocolate flavor without tasting of coffee.

Substitutions

Dutch-process cocoa

Natural cocoa works and gives a redder, tangier syrup. Black cocoa makes it very dark and Oreo-like; mix it half-and-half with regular cocoa.

Dark chocolate

Leave it out for a leaner syrup that keeps slightly longer; add 1 tbsp more cocoa. Milk chocolate makes a sweeter, milder sauce.

Granulated sugar

Brown sugar adds a caramel note. Reducing sugar makes a thinner, more bitter syrup that also spoils faster.

Variations

White mocha sauce

Melt 120 g white chocolate into 120 ml hot milk with a pinch of salt. It contains dairy, so refrigerate and use within 5 days.

Mexican chocolate

Add ½ tsp cinnamon and a pinch of cayenne with the cocoa.

Troubleshooting

The syrup is lumpy

Dry cocoa clumped. Whisk the dry ingredients first and make a paste with a little water, or strain the finished syrup.

It tastes dusty or chalky

It was not simmered long enough. Return it to the heat for another 2 minutes.

It is too thick when cold

Stir in hot water a teaspoon at a time, or warm it briefly before using.

Storage

Refrigerate in a clean, covered container for about 2 to 3 weeks. It firms up when cold; warm briefly or let it sit out a few minutes before use. Discard if it smells sour or shows mold.