In a large pot filled with boiling water, cook the noodles for 1-2 minutes, until al dente. Rinse under cold water and drain in a colander. Set aside and chill in the fridge.
Cook the eggs:
Crack the eggs into a glass bowl and beat until scrambled. Heat a large frying pan with a little oil over medium high heat and pour about half the mixture into the pan so it fries up like a thin omelette.
Cook for about 2 minutes and flip. Remove from pan and let cool before rolling it and slicing into thin strips.
Prepare the sauce:
In a small bowl, combine the ponzu, water, and sesame oil. Stir well. Add the sesame seeds on top.
Assemble:
When ready to serve, portion the cold noodles into bowls and arrange the eggs, ham/meat, cucumber, carrot, tomato, shrimp (and whatever toppings) over top the noodles. Pour the sauce over the noodles, mix well and enjoy immediately.
Notes
*If you can't find ponzu, just substitute 4 tablespoon soy sauce, 1 tablespoon lime juice, 1 tablespoon water, and 1 tablespoon sugar and mix together.