Porcini Fondue (Fondue aux Bolets) with Rosemary Roast Potatoes

Method

1. Preheat the oven to 200 °C. Put the dried porcini in a small bowl, pour over the hot water and leave to soak for 20 min. Keep the soaking liquid: it gives the fondue a deep, woodland flavour.

   Add in this stepDried porcini mushrooms 10 gHot water (for soaking) 100 ml

2. Halve the potatoes and toss with the olive oil, coarse salt and the rosemary needles, then spread them cut side down on a baking tray. Roast in the oven at 200 °C for 25 min, turning once halfway, until golden outside and fluffy inside.

   Add in this stepSmall potatoes, skin on 300 gExtra-virgin olive oil 1 tbspCoarse sea salt ½ tspRosemary sprigs 1

   oven

3. Cut the sourdough into 2.5 cm cubes, crust on, spread them on a second tray and put them in the oven when the potatoes are nearly done, for 5 min. They should be crisp outside but still soft inside, so they hold the fondue without going soggy.

   Add in this stepSourdough or rustic country bread 300 g

4. Trim the rinds from the Gruyère and Vacherin, grate coarsely or chop small, then sprinkle over the cornflour and toss well. With every shred coated in starch, the cheese melts into a smooth emulsion instead of clumping.

   Add in this stepAged Gruyère (12 months or more) 200 gVacherin Fribourgeois 200 gCornflour (cornstarch) 1½ tsp

5. Lift out the porcini, squeeze them and chop finely; strain the soaking liquid through a sieve lined with paper towel to remove any grit. Halve the garlic and rub it around the inside of a 18 cm fondue pot, then melt the butter and sweat the shallot and porcini over medium-low heat for 3 min, until the shallot is translucent but not coloured.

   Add in this stepGarlic clove 1Butter 15 gShallot 30 g

   medium-low heat

6. Pour in the wine, the strained mushroom liquid and the lemon juice and simmer over medium heat for 2 min to soften the raw alcohol edge and concentrate the flavour slightly.

   Add in this stepDry white wine (such as Chasselas) 130 mlLemon juice 1 tsp

   medium heat

7. Turn down to medium-low heat and add the starch-coated cheese a handful at a time, stirring in a figure-of-eight and waiting for each handful to melt before adding the next; it takes about 7 min in all. When it is smooth and creamy, add the kirsch, stir for 1 more minute, then finish with pepper and nutmeg. Never let it boil.

   Add in this stepKirsch (cherry brandy) 1½ tbspFreshly ground black pepper 1 pinchGround nutmeg 1 pinch

   medium-low heat

8. Move the pot to the fondue burner on the table, keep it on a low flame and serve with the roast potatoes and sourdough. Stand the burner on a flat, heatproof surface and never refill the fuel while it is lit. Scrape out the cheese crust at the bottom at the end.