For the béarnaise reduction:
- 300mls tarragon vinegar
- 3 large or 6 small shallots, chopped
- 2tbsp dried tarragon
- 1/2tbsp coarsely crushed black peppercorns
For the béarnaise sauce:
- 3 egg yolks
- 200g unsalted butter, melted
- A little salt and white pepper
- The leaves from 3-4 sprigs tarragon, finely chopped
- 2 x 200g fillet steaks
- Salt and pepper
- A little olive oil
- 2 large Maris Piper potatoes, peeled, cut into chips, well washed in cold water, drained and dried
- Fine salt
- Oil [vegetable or peanut, for instance], for deep frying
- To make the béarnaise reduction, put all the ingredients into a stainless steel saucepan and bring up to a boil. Reduce to a low simmer and cook, uncovered, until the mixture has reduced by half; about 30 minutes. [Note: have the extract on full whack, as the reduction is very strong.]
- Suspend a fine sieve over a bowl and pour the mixture into it. Using a small ladle, press down on all the tarragon/shallot mixture until no more liquid emerges below. Decant into a small bottle or jar and keep in the fridge until needed, where it will keep for months.
- To make the béarnaise sauce, whisk together the egg yolks in a stainless steel pan [preferably with rounded contours in the base of the pan, where the whisk won't miss any egg yolk] with a splash of water, over a low heat, until thick and smooth.
- Off the heat, now continue to whisk while pouring in the melted butter [remove any surface scum] in a thin stream, leaving behind the milky residue that has settled in the bottom of the butter pan.
- Once the sauce is smooth and glossy, add dribbles of the béarnaise reduction to the sauce until well flavoured, but not too vinegary; a scant tablespoon, say.
- Stir in the tarragon and correct seasoning. Decant into a serving bowl and keep warm over a pan of hot - not boiling - water while you grill the steaks
For the Chips
- Heat the oil to 140C. Put the potatoes into the frying basket and carefully lower them into the oil. Fry for about 7-8 minutes, lift them out and pinch one to see if they are soft. At this stage, you do not want them to colour; if you notice that they are turning a touch golden, then turn the temperature down a little.
- Now tip these floppy chips out onto a paper-lined tray and leave to cool while you cook the steaks. You may also do this stage a few hours in advance, keeping the chips covered, in the fridge.
- To finish the chips, turn the frying temperature up to full; on most machines, this is around about 180C [I actually think you need 190C, for the most crisp of chips, so search around for a deep-fryer that has this higher temperature]. Return the chips to the oil and fry again for 1-2 minutes, or until they are crisp and golden. Sprinkle with fine salt and serve at once.
For the Steak
- Season the steaks, brush with olive oil and cook on a ribbed, stove-top grill until done to your liking.
- Allow the steaks to rest for five minutes while you finish frying the chips.