Cut the pumpkin into slices and remove the seeds. Cook the slices in the oven at 200°C for about 1 hour. The pumpkin is soft enough when the skin can easily be removed from the pulp. Simply check in between with a wooden skewer to see if the flesh is already soft.
Peel the pumpkin slices while still warm, press them into a bowl with a potato press and add salt. Let the pumpkin puree cool down and mix it with egg and flour to form a smooth mixture. The gnocchi dough is ready when bubbles appear on the surface. It should be light and not stick to your fingers.
Roll the dough into finger-thick rolls. Traditionally, by rolling these rolls over a gnocchi board, the gnocchi get their typical regular grooves, which later absorb the sauce better. You can also create the grooves with a clean, wide-toothed hair comb.
Then cut bite-sized gnocchi and lay them on a kitchen towel. Gradually put them in lightly boiling salted water, reduce the temperature (remove the pot from the stove if necessary) and let them simmer for 2-3 minutes. When the pumpkin gnocchi float to the surface, remove with a skimmer and drain well.
In the meantime, melt the butter in a pan, add the sage leaves and heat briefly. The butter should not turn brown. Season the pumpkin gnocchi with the melted sage butter and plenty of grated Pecorino and serve immediately.