Cook the soba noodles in plenty of boiling, salted water for about 8 minutes. Drain, refresh in cold water and set aside.

For the broth
Bring to the boil 1,2 l water, stir in the dashi and cook for 5 minutes.

Add the bonito flakes and cook for a further 5 minutes. Strain the broth through a sieve and season with soy sauce and sake.

Wash and sort the spinach and cook in a little boiling, salted water until it collapses. Then drain, refresh in cold water and drain thoroughly.

Trim and wash the spring onions and cut into rings.

For the poached eggs
Put 2 l water into another pan, bring to the boil and then turn down to a simmer. Add the salt and vinegar.

Break each egg separately into a cup and carefully slide into the simmering water. Poach for 3-4 minutes.

To serve, put some noodles, spinach and 1 poached egg into each bowl and pour the boiling hot broth over. Scatter with spring onion rings and offer shichimi togarashi to season.