Peel and dice the pumpkin and sauté it in a non-stick pan with a drizzle of olive oil and the chopped onion. Add a few rosemary needles, thyme, and a few chopped sage leaves, pour in a glass of water, cover with a lid, and cook over low heat for 10-15 minutes, until you can mash the pumpkin with a fork. Once cooked, add salt and pepper and leave to cool.