Here is how to make hazelnut syrup: dissolve equal parts sugar and water into a clear simple syrup, then steep crushed toasted hazelnuts in it off the heat for 30 to 60 minutes, stir in a splash of vanilla, and strain well through a fine sieve or cloth. The result is a warm, toasty, nutty coffeehouse syrup you can stir into lattes, cappuccinos, iced coffee, and cold foam.
Homemade has one clear advantage over the bottle: you decide how toasty and how sweet it gets, and you know exactly what is in it — real nuts, sugar, water, and a little vanilla. Below is what the syrup actually is, the two ways to make it, a full ingredient list, the step-by-step method, how much to use per drink, and how to store it safely.
What hazelnut syrup is (and how it flavors coffee)
Hazelnut syrup is a plain simple syrup — equal parts sugar and water, cooked just until the sugar dissolves — carrying the toasted, praline-like flavor of hazelnuts. That flavor is the only real difference between this and a vanilla syrup or a caramel syrup: the same sweet base, a different aroma stirred through it. General simple-syrup technique — the ratios, why you heat it, how to keep it clear — lives in that vanilla guide, so this article stays focused on the hazelnut part.
As a coffee add-in it delivers the classic "nutty latte" note you know from cafe menus. A spoonful in a latte or cappuccino gives that rounded, toasty sweetness that pairs so naturally with espresso; a hazelnut latte syrup is exactly this, stirred into the shot before the milk goes in. It is just as good in iced coffee and cold brew, where it dissolves instantly, and folded into cold foam for a nutty crown. If you like warm-spice profiles too, a hazelnut syrup and a homemade chai syrup layer nicely in the same cup.
The two routes: real toasted nuts vs a quick extract version
There are two honest ways to build this hazelnut syrup recipe, and they trade effort for shelf life.
The first is a real toasted-hazelnut infusion: you toast and crush actual hazelnuts and steep them in the hot syrup. This gives the deepest, most authentic toasty flavor, but because you are steeping real nuts and their oils into the syrup, it comes out slightly cloudy and does not keep as long.
The second is a quick version that skips the nuts and stirs a little pure hazelnut extract (or nut flavoring) into a plain simple syrup. It is faster, clearer, and keeps longer, though the flavor reads a touch more one-note than a real infusion. Pick by what you want — depth or convenience.
| Route | Flavor | Keeps (refrigerated) |
|---|---|---|
| Real toasted-hazelnut infusion | Deep, toasty, praline-like; slightly cloudy | About 2 weeks |
| Quick hazelnut-extract syrup | Clean, direct, more one-note; clear | About 1 month |
Ingredients
This makes roughly a cup of syrup, enough for many drinks. The core is just sugar and water; the hazelnut flavor comes from either the nuts or the extract, not both.
| Component | Amount | Note |
|---|---|---|
| Water | 1 cup (240 ml) | Filtered if your tap water tastes strongly of anything |
| Granulated sugar | 1 cup (about 200 g) | Equal parts sugar and water is the cafe-standard 1:1 simple syrup |
| Toasted hazelnuts (real-nut route) | 3/4 to 1 cup (about 100 g) | Raw hazelnuts you toast and lightly crush; the deepest flavor |
| Pure hazelnut extract (quick route) | 1 to 2 tsp | Use instead of the nuts; stir in off the heat and start low |
| Vanilla | 1/2 tsp extract | Rounds out and softens the nuttiness |
| Salt (optional) | A small pinch | Lifts the flavor so it does not taste flat |
Gear is minimal: a small saucepan, a spoon, a fine strainer plus a piece of cheesecloth or a coffee filter, a funnel, and a clean glass bottle or jar with a tight lid. That is the whole kit.
How to make hazelnut syrup step by step
This is the real toasted-nut method, which is where the best flavor lives. The quick extract route follows right after.
- Toast the hazelnuts. Spread raw hazelnuts in a dry pan over medium heat or on a tray in the oven and toast until fragrant and golden, a few minutes, shaking so they color evenly and do not scorch. Toasting is what builds the deep, nutty character, so do not skip it.
- Crush them lightly. Let the nuts cool, then roughly crush or chop them. More cut surface means more flavor pulled into the syrup; there is no need to grind them to a paste.
- Warm the syrup until clear. Add 1 cup sugar and 1 cup water to the saucepan over medium heat and stir until the sugar fully dissolves and the liquid runs clear, usually 3 to 5 minutes. A gentle simmer is plenty — do not boil it hard, since you want to dissolve the sugar, not reduce it.
- Steep off the heat. Pull the pan off the burner, stir in the crushed toasted hazelnuts, and let them steep 30 to 60 minutes. Longer steeps pull more flavor; taste with a clean spoon toward the end and stop when you like it.
- Add the vanilla and salt. Once the syrup has infused, stir in the vanilla and the optional pinch of salt. These round the nutty note and keep the syrup from tasting flat.
- Strain well. Pour the syrup through a fine sieve lined with cheesecloth or a coffee filter to catch every bit of nut. Straining thoroughly matters here, because leftover solids and oils are what turn a real-nut syrup rancid fastest.
- Cool and bottle. Let the syrup come to room temperature, funnel it into a clean bottle or jar, seal, refrigerate, and label it with the date you made it.
For the quick route, make the plain 1:1 simple syrup as in step three, take it off the heat, then stir in 1 to 2 teaspoons of pure hazelnut extract plus the vanilla — start low, taste, and add more only if you want it bolder — then cool and bottle. There are no nuts to strain, so it comes together in minutes and stays clear.
How much hazelnut syrup to use per drink
Dose roughly 1 to 2 tablespoons of hazelnut syrup for coffee per drink and adjust to taste, starting low since you can always add more. Because it is already liquid, it blends into both hot and cold drinks without the grit of granulated sugar. For a hazelnut latte, stir the syrup into the espresso first, then add steamed milk; the full milk-and-ratio build lives in our latte at home guide, and you simply swap in this syrup. In iced coffee or cold brew, a spoonful stirs straight in and dissolves instantly.
Real-nut vs extract: what to expect in the bottle
It is worth setting expectations before you pour. A real-nut infusion comes out cloudier than the extract version, because you have steeped nut solids and oils into the syrup — that haze is normal and not a fault. It also means the real-nut syrup keeps for a shorter time: the same oils that give it depth are what eventually go rancid. Treat it as a make-a-little, use-it-up syrup rather than a big batch you store for months. The extract version, with no nut oils, stays clear and lasts noticeably longer.
How to store hazelnut syrup and how long it keeps
Keep the bottle sealed in the refrigerator. The real toasted-nut version is best used within about two weeks; the extract version holds up closer to a month. Pour it directly or use a clean spoon each time, never one that has touched another drink, so you do not introduce anything that speeds spoilage.
Give it a look and a sniff before each use. Any sour, rancid, or off smell, a texture that has turned cloudy-slimy, or fuzz on the surface all mean the batch is done — when in doubt, throw it out and make a fresh cup. If you want a little more shelf life, a higher 2:1 sugar-to-water ratio keeps somewhat longer.
A quick safety note
The one thing to flag clearly: this syrup contains tree nuts. Hazelnut is a common tree-nut allergen, so do not serve it to anyone with a nut allergy, and label your bottle if others share your kitchen. The quick extract route is not automatically nut-free either — many hazelnut extracts and flavorings are made from or processed alongside nuts and still carry allergen warnings, so always check the bottle. Beyond the allergen, treat it like any homemade syrup: keep it refrigerated, use clean utensils, and discard it if it smells off. Responses to nuts vary and this is a flavor guide, not medical advice; anyone unsure about a nut allergy should ask their own healthcare provider.
Once a bottle is cooling on the counter, a hazelnut latte or a nutty iced coffee is a single pour away. Make it once, keep it in the fridge, and you will reach for that toasty spoonful far more often than you expect.