Pre heat oven to fan forced 180ºC. Line large shallow rectangular baking tray with baking paper and line the tray with the puff pastry including the sides.
Lay fillings on the pastry. Spinach, ham then mushrooms.
Place cheeses into the Thermomix bowl and mill for 10 sec/speed 8. Set aside.
Place remaining ingredients into the Thermomix bowl with half the grated cheese and mix 8 sec/speed 6. Pour over fillings making sure not to over fill.
Top with remaining cheese and bake for 20-25 minutes until puffy and golden.