For the Compound Butter: Soften the butter (do not melt) add all the ingredients and mix well before placing on Greaseproof paper and roll into a cylinder 1-2cm in diameter.
Refrigerate and when firm, slice into chunks.
For the Burgers: Lightly season the mince and mix in the zest. Separate into four 200g balls of mince.
Use a ring or pastry cutter and mould half of each ball into the ring. Place a piece of prepared butter in the centre and cover with the other half of minced venison, mould into a burger shape.
Repeat for the remainder of the minced venison. To cook the burgers, shallow fry in sunflower oil for 3 minutes on each side.
Please keep the meat medium rare as venison is very dry when cooked well done. If you only will eat well done meat replace 200g of minced venison with the same quantity of minced pork and cook through.
For the Salsa - (best to make 1hr in advance): In a sauce pan heat the vinegar and sugar and reduce to a light syrup and remove from the heat.
Next add the soy sauce, then the onion, chilli and apple, mix well.
Finish the salsa with the olive oil and sesame oil and finally the lime juice, and correct the seasoning. Leave to rest at room temperature.
To Serve: Cut the buns in half and toast. Mix the mayo and horseradish together and spread on the toasted buns.
Place the venison burgers on the base bun, the cheese next and melt. Add the salsa and the top of the bun.
Skewer with your favourite pickles and serve with chips and salad.