Season the venison loins all over with freshly ground black pepper and some of the ground juniper berries.
Roll each seasoned venison loins tightly in heatproof cling film to form two sausages.
Bring a saucepan of water to the boil, then reduce the heat until the water is simmering at roughly 65C/150F (use a thermometer to check the temperature).
Add the wrapped venison loins, then return the water to 65C/150F and simmer for 15 minutes.
Remove the poached venison loins from the water, remove the cling film and set aside.
Meanwhile, heat a frying pan over a medium to high until hot, then add half of the butter. When the butter is foaming, add the poached venison and fry for 30-45 seconds on each side, or until just browned all over. Remove from the pan and rest for five minutes.
Bring the sugar and vinegar to the boil into a non-reactive saucepan, then add the remaining ground juniper berries and cook, stirring regularly, until the mixture has thickened enough to coat the back of the spoon.
Add the parsnip ribbons, in batches if necessary, and boil for 5-10 minutes, or until tender. Remove from the poaching liquid, shake off any excess liquid, and set aside. Keep warm. Repeat the process with the remaining parsnip ribbons, if necessary.
Bring the chicken stock to the boil in a separate saucepan, then reduce the heat until the mixture is simmering. Whisk in the remaining butter, then add the kale and cover the pan with a lid. for 5-10 minutes, or until just tender, then season, to taste, with salt and freshly ground black pepper.
To serve, carve each venison loin into three slices. Place three of the slices in a line down the centre of each plate. Top each piece of venison with some of the sweet-and-sour parsnip ribbons. Place half of the pear ribbons alongside each portion of venison, then drizzle over a little olive oil and season, to taste, with salt. Spoon the kale alongside. Spoon over the red wine gravy.