Preheat your oven to 180°C (350°F). Gather your ingredients for a smooth cooking process.

Spray a large frying pan with low-calorie cooking spray over medium heat. Sauté diced chicken and chopped onion for 5-7 minutes, until lightly browned.

Add the quartered mushrooms into the pan and continue cooking for another 5 minutes until softened.

Pour in white wine vinegar and Worcestershire sauce, then add chicken stock and let simmer for 5 minutes to meld the flavors.

Mix cornflour with a little water to create a slurry, then add to the pan, stirring until sauce thickens.

Fold in the quark (or low-fat cream cheese), seasoning with salt and pepper to taste.

Transfer the filling into an ovenproof dish, spreading it out evenly.

Cut the filo pastry into eight pieces, scrunch lightly, and layer over the filling. Spray the tops with cooking spray.

Bake in the oven for 15-20 minutes until the top is golden brown.

Remove from the oven and let cool for a minute before serving hot.