Awase Dashi, umami, rich, and flavor as deep as any other good stock. Awase dashi is a combination broth made using kelp (kombu) and bonito flakes (katsuobushi).
Simmer kelp for 10 minutes (then remove the kelp). Bring the water to a boil, then add bonito flakes (turn off the heat immediately). Steep the bonito flakes for 10 minutes and then strain the broth.