Cut sausage and kimchi into bite-sized pieces.
Julienne the onion.
Heat cooking oil in a pan and stir-fry the sausage.
Add kimchi and onion and stir-fry together.
Season with sugar, chili powder, and soy sauce.
Top cooked rice with stir-fried sausage and kimchi mixture.
Garnish with green onions and sesame oil as desired.