Remove the skin and seeds from the sweet pumpkin and cut it into bite-sized pieces.
Steam the sweet pumpkin for 15 minutes and let it cool.
Slice cucumber and onion thinly.
Place the steamed and cooled sweet pumpkin in a bowl and mash it with a fork.
Add cucumber, onion, and boiled egg to the mashed sweet pumpkin.
Add mayonnaise, salt, and pepper, then mix well.
For garnish, add some nuts or parsley if you prefer.