Wash and cut cherry tomatoes in half.

Thinly slice the red onion.

In a bowl, combine the tomatoes, onion, olive oil, lemon juice, white balsamic vinegar, and honey.

Mix well and set aside to marinate.

Boil buckwheat noodles according to package instructions, then rinse in cold water and drain.

Mix tsuyu and water to create the cold broth.

Place the cooked noodles in a serving bowl.

Top with the marinated tomato mixture and pour in the broth.

Thinly slice the perilla leaves.

Garnish with the perilla leaves and serve.