- 2 large free-range eggs, yolks only
- 2 tsp good-quality Dijon mustard
- 1 tsp English wholegrain mustard
- 3-4 tsp white wine vinegar, or to taste
- 150ml/5fl oz sunflower oil
- 50ml/2fl oz good-quality extra virgin olive oil
- pinch salt
- 1 small celeriac
- 1 bunch fresh dill, chopped
- 4 large floury potatoes (preferably Maris Piper), cut into fries
- sunflower oil, for deep frying
- salt, to taste
- 500g/17oz venison mince (preferably sirloin mince from fallow deer)
- salt and freshly ground black pepper
- 1-2 tbsp olive oil
- 1 red onion, finely sliced into rings
- 3 gherkins, drained, sliced
- 4 soft white bread rolls, cut in half horizontally
- tomato ketchup
- For the celeriac remoulade, place the egg yolks, mustards and vinegar into the bowl of a food processor and blend until well combined.
- With the motor still running, gradually add the sunflower oil in a thin stream, until the mixture thickens and becomes smooth and glossy. (If the mayonnaise starts to thicken too quickly, loosen it with the tiniest drop of warm water, then continue.)
- Add the olive oil in the same way, until the mixture is creamy in texture. Taste and add a drop or two more vinegar, if necessary. Season to taste with salt.
- Peel the celeriac, then slice to a 1mm thickness using a mandolin or very sharp knife. Pile the celeriac slices on top of each other, then cut the slices into thin strips using a sharp knife. Work as quickly as possible to prevent the celeriac from discolouring. Alternatively, grate the celeriac.
- Mix the celeriac with the dill in a large mixing bowl, then add enough mayonnaise to bind it together. Set aside for 30 minutes.
- Meanwhile, for the chips, rinse the potato fries under cold water, then drain well and pat dry using kitchen paper. Dry as thoroughly as possible.
- Heat the oil in a deep-fat fryer to 140C/285F. Alternatively, heat the oil in a deep-sided, heavy-based pan until a breadcrumb sizzles and turns golden-brown when dropped into it. (CAUTION: hot oil can be dangerous. Do not leave unattended.)
- When the oil is hot, add the chips (in batches if necessary) and fry for three minutes. Remove from the pan using a slotted spoon and set aside to drain in a colander lined with kitchen paper.
- Increase the heat to 180C/350F, then return the chips to the hot oil and fry for five minutes, or until lightly golden-brown. Remove from the oil again and drain in the colander (lined with fresh pieces of kitchen paper). Season with salt and keep warm.
- For the venison burger, season the venison mince with salt and freshly ground black pepper. Shape the seasoned mince into four thick burgers. Rub each burger all over with a little olive oil.
- Heat a griddle pan over a medium to high heat. When the pan is smoking, add the burgers and cook for 3-4 minutes on each side (for medium), or until brown griddle marks have appeared on the outside of the burgers and the burgers are cooked to your liking.
- To serve, place each burger into a bread roll and top with red onion, gherkins and a dollop of ketchup, if desired. Place the burgers onto four plates. Serve the chips and celeriac remoulade alongside.