Moules-Frites

Ingredients

• For the mussels
• 2 kg fresh mussels, bouchot mussels from the Côte d'Opale preferred; scrubbed and debearded
• 4 shallots, finely diced
• 50 g unsalted butter
• 300 ml dry white wine, or a blonde beer in the Flemish tradition
• 1 handful flat-leaf parsley, roughly chopped
• 1 grind black pepper
• For the frites
• 1 kg Bintje potatoes, or another floury, golden-fleshed variety; peeled, cut into 1 cm sticks
• 2 litres beef tallow (blanc de boeuf) or vegetable oil, sufficient for deep-frying; tallow is the traditional fat
• to taste fine salt, applied immediately after the second fry

Method

1. 1
   Peel the potatoes and cut into sticks of 1 cm thickness. Rinse under cold running water until the water runs clear, then dry thoroughly in a clean cloth. Any residual moisture will cause violent spattering and steaming in the fat rather than true frying.
2. 2
   Heat the frying fat to 150 °C. Working in batches, lower the dried potato sticks into the fat for 7–8 minutes — the blanchir stage. The frites should be cooked through but entirely pale, without colour. Lift out, drain, and spread in a single layer. Rest for a minimum of 30 minutes, and up to several hours. During this rest the moisture inside the potato redistributes and the first crust sets; without this interval the second fry cannot do its work.
3. 3
   This step decides the dish. Raise the fat to 180 °C. Return the rested frites to the fat for 2–3 minutes — the rissoler stage. The exterior must emerge deeply golden and audibly crisp; the interior, when broken, should be creamy. Season immediately and without hesitation with fine salt. A single fry produces a limp, greasy result; only the double fry, with its full rest between, creates the internal creaminess and external crispness that define a proper frite.
4. 4
   While the frites rest after their first fry, begin the mussels. In a large lidded pot — one large enough that the mussels fill it no more than two-thirds — melt the butter over a medium flame and sweat the diced shallots until soft and translucent, without colour.
5. 5
   Pour in the white wine (or blonde beer) and bring to a vigorous boil. Add all the mussels at once, cover immediately with the lid, and shake the pot vigorously. Cook for 4–5 minutes, shaking the pot at intervals to distribute heat evenly and ensure all mussels open. Discard without force any mussel that remains closed at the end of cooking.
6. 6
   Scatter the chopped flat-leaf parsley over the mussels and add a grind of black pepper. Serve the pot at the table as it stands, alongside the frites. An empty mussel shell serves as pincers for extracting the mussels; the accumulated pot liquor in the shell serves as the sauce for the frites.