Preheat the oven to 220°C Sift the flour into a bowl with a pinch of salt & pepper. Make a well in the centre of the flour. Whisk the eggs with the milk and chives, then pour this into the well in the flour. Gradually whisk the flour into the liquid to make a smooth batter. Cover and leave to stand for 30 minutes.
Put the fat into a roasting pan and place in the oven for 3-5 minutes. Add the sausages and cook for 15 minutes. Turn sausages twice during cooking.
Pour the batter over the sausages and return to the oven. Cook for about 20 minutes, or until the batter has risen and golden. Serve immediately.