Wash the sweet pumpkin thoroughly, remove the seeds, and cut into 2-3 cm pieces.
Place the sweet pumpkin in a steamer and steam for 15-20 minutes.
Put the sweet pumpkin in a bowl and mash finely with a fork.
Melt butter in a pan, add the sweet pumpkin, and sauté over medium-low heat for 2-3 minutes.
Season with salt and pepper.