Boil the noodles: Boil the chow mein noodles just short of al dente (you will finish them in the pan), rinse in cold water and set aside.
Cook the vegetables: In a large pan over high heat, add 2 tablespoons of oil, garlic and onions, and cook for 2 minutes. Add the rest of the vegetables and cook until they are almost soft but still yielding a crunch (about 8 minutes).
Add the noodles and seasonings: Lower the heat and add noodles, water, soy sauce, sake, rice vinegar, sugar and nori. Mix well and cook for a couple of minutes.
Make the omelets: Grab another pan to make your omelets. Whisk 2 eggs and set aside. Add 1 tablespoon of oil to a skillet and when the oil is hot, add the whisked eggs. Leave for a few minutes until the omelet is ready and transfer it to a plate. Repeat the same process until all 4 omelets are made.
Make the omurice: Equally divide the stir fried noodles and vegetables and push them to one side of each omelet. Fold the empty side over the stir fried noodles.
Serve: Top with tonkatsu sauce and kewpie mayonnaise and serve
Notes
This omusoba recipe taste best when eaten immediately. For leftovers, keep in a storage container and refrigerate for up to 2 days.