Pumpkin, spinach and ricotta pie with oregano and pine nuts | The Miller's Daughter

Ingredients

• 1 pumpkin, about 850g (1lb 14oz), peeled, cored and cut into cubes (see recipe introduction)
• 2 garlic cloves, finely chopped
• sea salt flakes and freshly ground black pepper
• 110g (3¾oz / scant ½ cup) extra virgin olive oil, plus about 60g (2oz / ¼ cup) for the filo (phyllo) pastry, plus more if needed and for the tin (pan)
• 300g (10½oz / 10 cups) spinach leaves
• 250g (9oz / generous 1 cup) ricotta cheese
• 80g (2¾oz) Parmesan cheese, grated
• 3 tbsp finely chopped oregano leaves, plus more to serve (optional)
• 7 sheets of filo (phyllo) pastry (my sheets were 48 x 25.5cm / 19 x 10in)
• 100g (3½oz / scant ½ cup) mascarpone cheese
• 30g (1oz / ¼ cup) pine nuts