Relevant blog post here.
Heat some oil in a pan on medium heat. Once hot, throw in the celery and cabbage with a tablespoon or two of water, so the cabbage doesn't burn. Dash salt over the veg.
While the veg is cooking, beat your eggs together with the mirin, fish sauce, and white pepper.
Once the veg is as soft as you like, pour the eggs over evenly. From here, cook the eggs however you like to cook scrambled eggs. (I like to let it sit until the sides are visibly set, then start to mix and agitate, so the eggs don't end up too firm or too soft.)
Stir in a sprinkle of sesame seeds and/or chia seeds if you like the texture, or want some extra fibre. Serve on its own, with rice, or as a side dish.