I made it per the recipe for the most part, and it turned out great, so I'll just reproduce the recipe for now.
The sauce is made up of three spoons of soy sauce, two spoons of oyster sauce, a spoon of dark soy sauce, a spoon of starch, and a spoon of sugar, plus half a cup of water and an appropriate amount of salt.
Green bell pepper, potatoes, and eggplant are chopped up into nice-sized pieces. The eggplant pieces get a nice powdering of starch so that so much oil is not absorbed. Each vegetable is (deep) fried separately. The pepper goes in and almost immediately comes out, the potato goes in for several minutes, but the marker is that it's soft and easily poked at with a chopstick. The eggplant is fried for about half the time, and is measured by a similar metric. Once all the vegetables are fried, get rid of most of the oil, leaving a tiny amount. Get a bit of garlic cooked, then add in the sauce, and veggies, and cook until most of the water has evaporated. Throw in some green onion at the end to seal the deal.