1. Water: 1 liter, kombu: 10 grams, bonito flakes: 10 grams, the ratio of ingredients to water is 1:100.

2. Soak the kelp in water for more than 30 minutes in advance to make the sweetness easier to release.

3. Put 10 grams of kelp into 1 liter of water, boil the water over medium heat, and then remove the kelp.

4. Turn off the heat, pour 10 grams of bonito flakes into the hot water, adjust the heat to medium to strong, when it boils again, turn to low heat, and pick up the bonito flakes. The bonito kombu soup is done.

5. After the bonito kombu soup has cooled down, it can be stored in the refrigerator. The recommended storage period is within 2 to 3 days.