Thinly slice the onion and soak it in cold water to remove the sharpness.

Boil the ramen noodles and the included flakes in boiling water. You can skip the flakes if preferred.

Rinse the cooked noodles and flakes under cold water and drain thoroughly.

Dissolve the ramen seasoning packet in 50ml of hot water.

Mix the dissolved seasoning with 1 tbsp each of vinegar, sugar, and sesame oil.

Place the drained noodles and flakes into a serving bowl.

Pour the prepared seasoning mixture over the noodles.

Add 200ml of cold water and ice to the bowl.