This is the perfect dish to take on your next picnic. You will need to cure the meat three days ahead. This curing process can also be used on a fillet of venison. If you don't eat it that day, it will be fine the next if kept in the fridge.
400g coarse sea salt
10 sprigs of rosemary
1 fillet of beef (ask your butcher to trim it)
a handful of finely cracked black pepper
1 head of celeriac, peeled
juice of 1 lemon
1 1/2 tbsp Dijon mustard
4 tbsp creme fraiche
sea salt and black pepper
1. Mix the salt and sugar together. Take a plastic container into which your fillet will fit uncured and which will fit in your fridge, and place five sprigs of rosemary in the bottom.
2. Generously cover with the salt and sugar mix, lay the fillet on to this, then cover with the rest of the mix (if you have not got enough of the salt and sugar mixture, simply make up some more, 40 per cent salt to 60 per cent sugar). Nestle the rest of the rosemary into this. Cover the container and refrigerate for three days.
3. Remove the fillet from the now damp salt and sugar, rinse under cold running water, and dry with a clean cloth. When dry, take a handful of cracked pepper and rub the firm fillet all over; this should remove any remaining moisture and give an oomph to the meat. Wrap in cling film and keep in the fridge until you use it.
NOTE: this is not a long curing process and as a result the meat will not keep for more than one week and should be refrigerated.
4. Slice the celeriac very thinly, using the width of a match as a rough guide, then lay a manageable pile of slices flat and slice again into match widths. At this point a mandolin is very useful but if you don't have one, do not fear; you can easily achieve matchstick strips of celeriac with a knife. As you go, squeeze lemon juice over your growing mound of celeriac strands to prevent them going brown when finished.
5. Fold the Dijon mustard and creme fraiche gently together – don't beat as the cream will lose its structure. Season to taste and mix this through the celeriac.
6. To serve the beef, slice thinly across. You will have beautiful dark red flesh – the colour of a fine old master comes to mind. The spirited wine celeriac makes a splendid accompaniment.
This is an edited extract from The Complete Nose to Tail by Fergus Henderson.
Also try Fergus' 'seed cake with Madeira'.