1. Preheat oven to 200°C and put a plate in the fridge. Sift the flour 3 times onto a sheet of grease proof paper.
2. Place the butter and water in a saucepan over a low heat to melt the butter. Then bring to a fast boil over a high heat so the liquid climbs sides of pan (rolling boil).
3. Turn off the heat and tip in the flour all in one go. Use a wooden spoon to slowly stir the flour to form a firm, smooth paste that then comes a way from the edge of the pan, forming a ball. When this happens, stop stirring.
4. Spread the paste smoothly in a thin layer onto the plate from the fridge then leave for 10 mins until body temperature. Lightly grease a baking sheet.
5. Return the paste to the pan, beat in the eggs, 1 tablespoon at a time, until the mixture has a reluctant dropping consistency (5-7 sec to drop), holding its shape but with a slight sheen. Add the cheese and seasoning.
6. Bake in the top third of the oven for 20-30 mins until puffed up and golden. Do not open the oven until done or they will collapse. Serve warm with chives on top.