Kongguksu (Korean Cold Soy Milk Noodles)

Method

1. Rub the soybeans between your hands in 2 or 3 changes of water, discarding any that float, then soak them in at least three times their volume of water for 8 h. In hot weather, soak them in the fridge so they don't sour. They're ready when a split bean is evenly yellow and flat inside.

   Add in this stepDried yellow soybeans 120 g

2. Drain the beans, put them in a 18 cm pot and cover with fresh water. Bring to the boil on high heat, then lower to medium heat and cook uncovered for 10 min, skimming off the foam. Taste one: it should be nutty with a slight bite and no raw, grassy taste. Undercooked beans taste raw; overcooked ones smell musty. Rinse at once in cold water to cool; for a silkier broth, rub off the skins and float them away.

   high heat→medium heat

3. Toast the sesame seeds in a dry pan on medium-low heat for 2 min, stirring, until a few pop and they smell nutty, then tip onto a plate to cool.

   Add in this stepSesame seeds 2 tbsp

   medium-low heat

4. Put the cooked beans, toasted sesame, cold water and half the salt in a blender and blend for 2 min, until almost no grit can be felt between your fingers. For an even smoother broth, pass it through a fine sieve. Chill in the fridge for at least 30 min.

   Add in this stepCold water (for blending) 550 mlSalt ½ tsp

5. Bring 2.5 L of water to a rolling boil in a large pot on high heat, add the noodles, fanned out, and cook for 3 min, stirring with chopsticks. If it threatens to boil over, add half a cup of cold water. Drain, then rub the noodles under cold running water to wash off all the starch, dip them in iced water and squeeze out the water well.

   Add in this stepThin wheat noodles (somyeon or junggukso) 200 g

   high heat

6. Cut the cucumber into fine matchsticks and the tomato into wedges. Put the noodles in bowls, pour over plenty of cold soy broth, float the ice on top and add the cucumber and tomato. Serve the rest of the salt, and sugar if liked, on the side so everyone can season their own.

   Add in this stepCucumber 80 gTomato 1Ice cubes 6Salt ½ tspSugar (optional, regional style) to taste