Line a 15cm square container with a double layer of cling film leaving an overhang.
Boil the leeks in 3 liters of salted water for 20 minutes until tender then cool completely.
Blend the vinaigrette ingredients with a teaspoon of water using a hand blender.
Layer the leeks in the container, brushing each layer with vinaigrette and adding truffle slices.
Fold over the film, add a weighted container on top, and compress for 12 hours.
Slice the terrine into 2cm thick pieces while still wrapped in film.
Remove the film and plate each slice using a palette knife.
Brush with chive vinaigrette and garnish with artichokes, extra truffle, and winter leaves.