Thinly slice the leek and crush the garlic.
In a non-stick pan over medium heat, melt the butter.
Sauté the leek and garlic until soft and tender.
Add chopped chicken, cook for 4 minutes, tossing to cook evenly.
Add mushroom, season and cook, 3 minutes.
Reduce heat and add cream, simmer for 20 minutes.
Meanwhile cut 6 small bases and lids from the pastry. Press the 4 bases into each base.
Top with a lid, cook for 8 minutes, or until the crust is golden brown and crunchy.
Carefully remove and repeat.