Cook onion and garlic in a large non stick pan. Add chicken mince. Cook until brown, Add mushrooms, beans and zucchini. Cook until soft.
Add mustard, stock, cream and tarragon. Cook until heated through.
Layer 3 sheets filo pastry together with cooking oil spray. Spoon 1/4 chicken mixture in the middle of one short end of filo. Roll up filo, folding in ends, to enclose filling.
Repeat with more filo and chicken mixture to make 4 pies.
Cook for 15 minutes at 200 degrees C for until browned. Serve with salad.