Preheat the oven to 200C/400F/Gas 6.
Rub a little olive oil over the venison fillet. Place the crushed black peppercorns onto a plate and roll the venison over the peppercorns to coat it, then sprinkle with salt.
Heat the 1 tbsp olive oil in a frying pan and place the venison into the pan to fry for 2-3 minutes on each side, or until cooked to your liking. Set aside to rest in a warm place.
For the red wine vinaigrette, place the red wine, chopped shallot, vinegar and sugar into a small saucepan and simmer over a high heat for 8-10 minutes, or until reduced by half. Remove the pan from the heat, add the herbs to the vinaigrette and set aside in a warm place.
For the roasted tomatoes, place the tomatoes, garlic, olive oil and cobnuts into a small roasting tin, season well with salt and freshly ground black pepper and stir to mix.
Transfer the tomatoes to the oven to roast for 10-12 minutes, or until softened and slightly charred at the edges. Remove the garlic cloves and discard.
To serve, slice the venison fillet into thick slices and place onto a serving plate with the roasted tomatoes on top and the vinaigrette poured over.