Clean and peel the pumpkin and cut 2 cm pieces. Place in salted water for 2 hours. Then drain in a sieve. Place on a few sheets of kitchen paper and dry thoroughly.
Fry briefly in 6 tablespoon olive oil in a large pan, turning so that the pumpkin pieces are lightly browned on all sides. But not for too long, otherwise the pumpkin pieces will dissolve. Remove and degrease a little bit of oil on a sheet of kitchen paper.
Chop 4 cloves of garlic and fry together with 8 sage leaves in the remaining oil until the garlic has taken on some color. Deglaze with 4 teaspoons of white wine vinegar, add the pumpkin pieces and olives, cover and let simmer together for a few minutes.
Serve garnished with peppermint leaves if you like.