1. Roast kombu in 350 degree oven for about 10 to 15 minutes, or until they are dark and crisp but not burnt. 

2. Crush and grind the seaweed in a suribachi until it becomes a fine powder.

Variation:

• Roast kombu in a dry skillet over the stove until dark and crisp. Cover and cook over a low flame so that the kombu does not bum. Turn when needed so that it roasts evenly.

• Crush and grind into a fine powder in a suribachi.