Hazelnut Syrup

Before you start

Most bottled hazelnut syrups are flavored with extracts. Making it from nuts gives a deeper, toasty and slightly buttery flavor. The process has three stages: toast the hazelnuts until fragrant and lightly golden inside, steep the chopped nuts in hot water to make a nut tea, then strain and dissolve sugar into that liquid.

Toasting is where the flavor comes from, so do not skip it or rush it. Pale nuts give a weak, grassy syrup; burnt nuts make it bitter. Chopping the nuts before steeping exposes more surface, and measuring the strained liquid before adding sugar keeps the ratio a true 1:1, since the nuts soak up some water.

Ingredients

• 150 g (1 cup) raw hazelnuts
• 360 ml (1½ cups) water
• about 250 g (1¼ cups) granulated sugar — match the weight of the strained liquid
• 1 small pinch fine salt
• ¼ tsp vanilla extract — optional

Method

1. Heat the oven to 175°C (350°F). Spread the hazelnuts on a baking sheet and toast for 10 to 12 minutes, until the skins crack and the nuts smell strongly toasted. Cut one in half; the inside should be light golden.
2. Tip the hot nuts into a kitchen towel, wrap them up and rub vigorously to remove most of the papery skins. Some skin left on is fine.
3. Roughly chop the nuts or pulse them in a food processor into coarse pieces, about the size of rice grains. Do not grind into a paste.
4. Bring the water to a boil in a small saucepan. Add the nuts, lower the heat and simmer for 5 minutes. Remove from the heat, cover and steep for 1 hour.
5. Strain through a sieve lined with cheesecloth, pressing on the nuts to extract the liquid. Weigh the liquid; you should have about 250 g.
6. Return the liquid to the clean pan with the same weight of sugar and the salt. Warm over medium-low heat, stirring, until the sugar dissolves, about 2 minutes. Cool for about 15 minutes, stir in vanilla, and bottle.

Tips for success

• Dry the strained nuts in a low oven and use them in granola or baking; they still have some flavor and plenty of texture.
• A few drops of pure hazelnut extract boost a syrup that tastes too light, but taste first; real toasted flavor usually needs none.
• Use 15 to 20 ml per latte. It pairs especially well with mocha sauce.

Substitutions

Hazelnuts

Pecans or almonds work the same way; pecans give a maple-like syrup and almonds a gentle, marzipan-like flavor. Keep the same toast and steep method.

Granulated sugar

Light brown sugar adds a praline note that suits hazelnut. Use the same weight.

Steeping time

For a stronger syrup, steep overnight in the fridge after the initial simmer, then strain and sweeten.

Variations

Hazelnut cocoa

Whisk 1 tbsp cocoa powder into the warm syrup for a chocolate-hazelnut version.

Rich hazelnut

Use 2 parts sugar to 1 part liquid by weight for a thicker syrup that keeps a little longer.

Troubleshooting

The syrup tastes weak

The nuts were under-toasted or steeped too briefly. Toast until golden inside and steep the full hour or overnight.

It tastes bitter

The nuts were over-toasted or too many skins remained. Watch the oven closely and rub off more skins.

It is cloudy with an oily film

Nut oils rise to the top. Refrigerate, then skim any solidified oil and strain through a coffee filter.

Storage

Refrigerate in a clean, sealed bottle and use within about 2 weeks. Nut infusions spoil faster than plain syrups. Discard if cloudy, sour-smelling or moldy.

Safety notes

Contains tree nuts, a major food allergen according to FDA. Label the bottle clearly and keep it away from anyone with a nut allergy.