Ham and zucchini quiche

Pastry

• 60 g cornflour
• 150 g plain flour, plus extra for dusting
• ½ tsp baking powder
• 1 pinch salt
• 150 g unsalted butter, chilled and cut into pieces
• 30 g cold water

Filling

• 50 g Parmesan cheese, cut into pieces (3 cm)
• 1 sprig fresh dill, leaves only
• 500 g water
• 800 g zucchini, deseeded and flesh cut into pieces (3-4 cm)
• 50 g olive oil
• 1 brown onion (approx. 120 g), cut into quarters
• 100 g ham, cut into pieces (approx. 1 cm)
• 4 eggs
• 50 g pouring (whipping) cream (optional)
• 1 tsp salt
• ½ tsp ground black pepper