Cut the broccoli into bite-sized pieces and wash thoroughly.
Add a little salt to boiling water and blanch the broccoli for 2-3 minutes.
Rinse the blanched broccoli in cold water and drain well.
Thinly slice the onion and carrot.
In a bowl, mix broccoli, onion, carrot, mayonnaise, salt, and pepper together well.
Transfer the finished salad to a serving dish.