Hazelnut Gelato Recipe: Toast the Nuts Yourself, Skip the Machine

The smell tells you before the timer does. Around minute eight the kitchen at Piazza Margana 22 goes from nothing to roasted hazelnut, and that is when people start opening the oven door to look. Two more minutes. The skins have to split and the kernel underneath has to be pale gold, and if you pull them at the smell the finished gelato tastes of raw nut.

This hazelnut gelato recipe is the one from our gelato workshop: whole hazelnuts you toast and grind yourself, a base of whole milk and cream sweetened with sugar and a spoon of honey, no eggs, no machine. The freezer does the freezing and a whisk does the rest, once every 30 minutes for 4 hours. It shares a freezer with our pistachio version, not a method: pistachio is blanched and ground raw, hazelnut is roasted, and the roast is most of the flavor. So this one earns its time in the oven.

Four cups come out of 120 g of shelled hazelnuts, 240 g of whole milk, 120 g of fresh cream, 80 g of sugar, 40 g of honey and a pinch of fine salt. Per person that is 30 g of hazelnuts, 60 g of milk, 30 g of cream, 20 g of sugar and 10 g of honey. Of the hazelnuts, 100 g go into the paste and 20 g get chopped for the top.

Buy the hazelnuts raw and shelled, skins on. The oven does the roasting and a cloth does the skinning. Pre-roasted nuts from the snack aisle are often months old, and old hazelnut oil tastes of cardboard. If a shop near you has Piedmont hazelnuts, use them: there are only 120 g in the recipe and nothing else is doing the flavor.

The cream is fresh liquid cream with at least 35% fat. Not a whipping product with stabilizers. The milk is whole.

The honey is a mild one, acacia if you can get it, a honey you cannot taste over the nuts. Chestnut would win that argument.

Single layer on a tray, 180 °C, 10 minutes, a shake at the halfway mark so the edge and the middle trade places. That is the whole procedure, and it still goes wrong more than any other step, because people judge the nut by its skin.

Cut one in half. The outside of a hazelnut is skin, and skin darkens long before the kernel does. What you want is the skins cracked and lifting and a kernel that is pale gold at the center. Not brown. A brown kernel has crossed into bitter, and more sugar does not balance that; it just becomes bitter and sweet. Under-toasted is the milder fault: pale paste, and a gelato that tastes mostly of milk.

We run the oven at 180 °C rather than hotter because a class is a room full of distractions, and 180 °C leaves some margin before the kernels go over. Then straight onto a clean cloth, because on the hot tray they keep cooking, and the distance between right and brown is about a minute.

Fold the cloth over and rub hard for a minute, while the nuts are warm. Cold, they cling. A few stubborn flecks do no harm.

The skin is where the tannin is. Leave it on and the paste goes brown-gray and the gelato finishes with a dry edge most people read as burnt. The Tonda Gentile grown in Piedmont, sold as Nocciola Piemonte IGP, is prized partly because its skin comes away cleanly in the oven. Other varieties hold on harder: rub longer.

Set 20 g aside for the top and put the other 100 g in the blender, still warm. Pulses of 20 seconds, scrape the sides, pulse again, 5 to 8 minutes in total. Three stages: a powder, then damp sand that packs against the blades, then the oil lets go and the whole thing turns glossy and starts to flow. Stop when it slides off a spoon. Warm nuts give up their oil faster.

Somebody always asks why we do not simply chop the nuts and stir them in. Because chopped hazelnut in gelato is a texture, not a flavor. The flavor lives in the oil, and in a chopped piece the oil stays inside the piece: you taste milk, then crunch, then nut. Ground to a paste, the oil is spread through every gram of the mix and the milk tastes of hazelnut from the first spoon. The 20 g on top are for crunch, and only that.

If you buy the paste instead, read the label: one ingredient, hazelnuts, sometimes called hazelnut butter in the UK and the US, and 90 g stands in for the 100 g of nuts. Hazelnut spread is sugar, palm oil and cocoa with the nuts last, and gelato made with it tastes of the jar.

A home freezer runs at about -18 °C, and a base of milk, cream and an ordinary amount of sugar sets into a brick at that temperature. A gelateria cabinet is warmer. We cannot change your freezer, so we change the tray.

Sugar lowers the freezing point, and honey lowers it more per gram than sugar does. That is why the sweetening is split: 80 g of sugar for taste and body, 40 g of honey for softness. Honey is mostly glucose and fructose, smaller molecules than table sugar, and smaller molecules keep more of the water unfrozen at -18 °C. Professional recipes use glucose syrup or dextrose for this, at the same weight; honey is what most kitchens have. All sugar and no honey, and after a night in the freezer you need a knife.

The cream is the other half of the softness. Fat does not turn into ice; it coats the crystals that form and keeps them apart, so the scoop bends instead of shattering. 240 g of milk to 120 g of cream is where the base still tastes of nut and holds a scoop.

No eggs, either. A custard base makes a fine gelato, but yolk has a flavor of its own and it sits on top of the roast. Without it the base only needs to reach 70 °C, enough to dissolve the sugar and honey.

Milk, sugar and honey first. 240 g of whole milk in a small pan with the 80 g of sugar and the 40 g of honey, low heat, stirring, about 5 minutes, until a thermometer reads 70 °C. Without one, pull it when the milk steams and the first tiny bubbles show at the rim.

Cream, paste and salt go in off the heat. 120 g of cream, the hazelnut paste and a pinch of salt. Stick blender, one full minute, head kept under the surface. The mix goes from streaky to an even beige. A ring of oil floating up means the milk proteins have not caught the nut oil yet: 30 seconds more. A head that breaks the surface whips air in, and a foamy base freezes into something closer to semifreddo.

Cold before the freezer. Pan into a bigger bowl of water and ice, a stir now and then, 30 minutes, until a finger in the base feels cold; the fridge gets there too, in 3 to 4 hours. The freezer works from the walls inward, and a warm base takes so long to reach zero that the first crystals grow long, and long crystals survive every whisk round that follows.

Then the freezer and the timer. A shallow steel container, the base no more than 2 to 3 cm deep, covered. From here the job is keeping the ice crystals too small to feel. A machine scrapes a frozen bowl nonstop; you do it by hand every 30 minutes: out, a hard whisk that drags the frozen rim into the soft middle, back in. Eight rounds over 4 hours. At 2 hours it looks like soft-serve; at the last round it keeps the marks of the whisk. Ten minutes on the counter, then scoop, with the 20 g of chopped hazelnuts on top.

These reach us by email the week after class, roughly in this order.

• Toasting by the clock. Ten minutes at 180 °C is our oven; a fan oven runs hotter, an old one cold. Look at minute eight and cut a nut before you trust the timer.
• Doubling the recipe in the same tray. Twice the base in one container sits 5 or 6 cm deep, and the middle is still liquid when the rim is rock. Two trays.
• Fixing the sweetness at the pan. The warm base should taste a shade too sweet, because cold mutes sugar. It is also not the place to add more: the 80 g and the 40 g decide how soft it freezes.
• The round that got forgotten. Forty-five minutes of conversation and the tray is a slab with a slush center. Whisking a slab gives you shards of ice in cream. Soften it 10 minutes, blitz it smooth with the stick blender, go back to the rounds. Gelato, just not as fine.

A cup shows the texture better than a cone, and it is how we serve it in class: two scoops, the chopped hazelnuts, nothing else. Rome puts hazelnut and pistachio in the same cup out of habit, and if you make the pistachio gelato as well, the two bases can do their freezer rounds side by side.

It keeps a week in the freezer in a sealed container and gets harder every day, because the freezer keeps pulling water into crystals. From the second day on, give it 15 minutes out and a turn with a spoon before scooping. What has melted does not go back in.

One variant worth making: hold back a spoonful of the paste and swirl it through at the last whisk round, for streaks of pure hazelnut in the scoop.

In our kitchen at Piazza Margana 22, in the historic center. The gelato making class lasts about 90 minutes and is built around the base: you prepare it from scratch with the chef, balance the ingredients and work on the texture, with no machine, so the method comes home with you. What a written recipe cannot show you is the color of a kernel cut in half and the second the paste lets go of its oil. The class opens with a welcome of Italian wines, espresso and traditional cookies, and pistachio and hazelnut are both on its sample menu. The same workshop also runs as a private session.

If you would rather make it after a pizza, the pizza and gelato class runs about two and a half hours: you make the dough from scratch, bake your own pizza and finish with gelato. Everything else we run is on the cooking classes page.