Fonduta valdostana is Valle d'Aosta's magnificent cheese fondue—cubes of Fontina DOP melted slowly with butter, milk, and egg yolks into a velvety, golden, gloriously rich cream that is served in warm bowls with croutons of toasted bread, or poured over polenta, vegetables, or used as a sauce for risotto and gnocchi. This is not Swiss fondue (which uses Gruyère, wine, and kirsch in a communal pot)—the Valdostan fonduta is a smoother, richer, more refined preparation that relies entirely on the unique melting qualities of Fontina DOP, the great Alpine cheese produced exclusively in the Aosta Valley from the milk of the indigenous Valdostana cattle breed. Fontina DOP is a semi-soft, washed-rind cheese aged 3-4 months with a distinctive earthiness, a melt that is incomparably smooth, and a fat content that produces the luxurious, coating consistency that defines fonduta. The preparation requires patience: cubed Fontina is soaked in milk for several hours (or overnight) to soften and begin breaking down. The softened cheese-and-milk mixture is then melted very gently in a double boiler (bain-marie) with butter, stirring constantly with a wooden spoon until smooth and homogeneous—the temperature must never exceed 60°C or the cheese will seize and become stringy. Once smooth, beaten egg yolks are whisked in off the heat, creating a custard-like richness that elevates the fonduta from melted cheese to something almost sauce-like in its refinement. The finished fonduta should coat a spoon and flow in lazy ribbons. The traditional serving is in pre-warmed individual bowls, each with toasted bread soldiers for dipping, and—in the most luxurious version—thin shavings of white truffle from nearby Piedmont scattered over the surface.
Use only Fontina DOP from Valle d'Aosta. Soak cubed cheese in milk for hours. Melt gently in a bain-marie, never exceeding 60°C. Stir constantly for smooth texture. Whisk in egg yolks off the heat. Serve warm in individual bowls with croutons. Optional white truffle shavings.
The Fontina must be genuine DOP—look for the Consorzio stamp on the rind. Cut the rind off and cube the cheese into 1cm pieces for even soaking. The bain-marie water should be barely simmering—even that may be too hot; adjust constantly. The egg yolks add richness and help stabilise the emulsion—whisk them in vigorously off the heat. If it breaks, a splash of warm milk and vigorous whisking can save it.
Using non-DOP or generic Fontina (the melting quality is incomparable). Heating too fast or too high (cheese seizes and becomes stringy). Skipping the soaking step (cheese won't melt smoothly). Adding egg yolks while too hot (they scramble). Letting it cool (it thickens and becomes clumpy). Confusing with Swiss fondue (entirely different preparation).
Touring Club Italiano, Valle d'Aosta in Cucina; Academia Barilla, Regional Italian Cooking