Steps

1. Wash 1 cucumber and cut off both ends.
   🕒 00:55
2. Slice the cucumber as thinly as possible into rounds.
   🕒 01:11
3. Place the thinly sliced cucumber in a large bowl, add 120ml of Mentsuyu (double concentrated) and mix. [Key Tip!] Soaking the cucumber in undiluted mentsuyu allows it to absorb the flavor well and release delicious juices.
   🕒 01:36
4. Thinly slice 2 myoga ginger bulbs.
   🕒 02:28
5. Roll 4-5 Japanese shiso leaves and thinly slice them.
   🕒 02:36
6. To the bowl of cucumber marinating in mentsuyu, add 250ml of water.
   🕒 02:57
7. Add 1 small can of canned tuna, including its oil.
   🕒 03:20
8. Add the sliced myoga ginger, 3g of bonito flakes, and 2 tbsp of ground white sesame seeds and mix.
   🕒 03:32
9. Add the thinly sliced Japanese shiso leaves and mix briefly.
   🕒 04:08
10. Chill the soup with plenty of toppings in the refrigerator.
    🕒 04:23
11. Boil 2-3 bundles of somen noodles in plenty of boiling water. Cook slightly less than the package instructions.
    🕒 04:31
12. Rinse the boiled somen noodles in cold water, vigorously rubbing to remove surface oil and salt.
    🕒 05:00
13. Thoroughly squeeze the water out of the rinsed somen noodles to prevent them from becoming watery.
    🕒 05:31
14. Place the drained somen noodles in serving bowls.
    🕒 05:43
15. Generously ladle the chilled tuna and cucumber soup over the somen noodles.
    🕒 05:51
16. Garnish with white sesame seeds (to taste) and black sesame seeds (to taste) as desired.
    🕒 06:08