Preheat the oven to 180°C (th.6) Spread out the pastry at the bottom of the mould. Cover with a sheet of baking paper, then place small cooking weights or dried beans on top and bake in the oven for 15 mins. During this time, cut the stems and remove the outer leaves of the fennel, keeping only the bulb. Then rinse it and slice it thinly.
Melt the butter in a large frying pan and slowly cook the fennel with the aniseed seeds for 15 minutes (adding a little water if necessary). Mix in the cream, the eggs and the nutmeg.
Remove the fennel from the pan and wilt the spinach for 1 min.
Remove the cooking weights from the pie base, arrange the slices of fennel and spinach on top and then pour in the cream and egg mixture.
Cut up the Reblochon into slices and arrange over the tart.
Place in the oven for 30 mins.
Serve the tart as soon as it comes out of the oven.