Stir the water, curing salt, mustard seeds, garlic granules, black pepper and liquid smoke in a large bowl until the curing mixture has dissolved. Mix in the minced venison, Cheddar cheese and chillies; mix until evenly blended and somewhat sticky, about 3 minutes. Divide the mixture in half and roll each half into 5cm thick logs. Wrap each log tightly with foil and refrigerate for 24 hours.
Preheat an oven to 150 C / Gas 2. Line a baking tray with foil, then remove the foil from the sausage logs and place them onto the baking tray.
Bake in the preheated oven until the internal temperature reaches 75 degrees C, 1 1/2 to 2 hours. Cool the sausages on a rack until they have cooled to room temperature. Dab occasionally with a kitchen towel to absorb excess fat. Slice thinly to serve.