Miso Yaki Onigiri

Ingredients:

320g (11.3oz.) cooked Japanese rice *I mixed some brown rice
2 tsp. toasted white sesame seeds *optional
* 1 tbsp. Miso
* 1 tbsp. Mirin (sweet Sake)
* 1/2 tsp. sugar
* a pinch of Dashi powder
2 tsp. sesame oil