Halve, deseed and chop the pumpkin into small pieces and rub them with a little olive oil. Bash up the coriander seeds, fennel seeds and chilli in a pestle and mortar with a good pinch of sea salt and black pepper and toss into the pumpkin, then put them into a roasting tray and bake for 15-20 minutes, or until golden. Pick the marjoram leaves and peel and finely slice the garlic. Get a large pan nice and hot and add a little olive oil, the herb leaves and sliced garlic. Move it all around for 20 seconds, then add the spinach.
Add a knob of butter and some freshly grated nutmeg and drain on kitchen towel. Lay out a tea towel then lay a sheet of pasta on top, spoon a line of pumpkin along the long edge of the sheet nearest you then sprinkle the spinach over the rest of the sheet, leaving the top 5cm of the pasta sheet clear.
Crumble the ricotta over the spinach, finely grate over the Parmesan and roll up in the tea towel, brush a little water to help the pasta stick. Then tie up the ends of the towel to secure the pasta roll inside. Simmer the rotolo submerged in water for about 25 minutes. Remove and rest. Brown the remaining butter, add the sage and a squeeze of lemon and pour over the pasta roll.