We couldn't come up with a better name for it, but nobody who's tried
it has disputed the claim that it's awesome.
See also "Variations" below.
The correct sauce to use is the unstoppable Lao Gan Ma [Old Dry Mother] chili sauce, also known as "Stern Lady Sauce." This is shredded chilies in oil, with MSG, Sichuan pepper, and peanuts. Extensive A/B testing has found no substitute that can really compare. You can try to make your own chili oil sauce or try using a similar product. Though it seems strange to claim that Sriracha chili sauce could be considered suboptimal in any context, data indicates that it's simply not as good as Lao Gan Ma for this dish. It's acceptable, of course.
If you can't find the real deal, you could consider slightly changing the nature of the dish by using a Chinese black bean sauce, Hoisin sauce or teriyaki sauce.
The preparation happens in four parts in parallel. They are listed below in order of decreasing preparation time; if you are able to fully parallelize them (i.e. have several large frying pans and a rice cooker), you can simply start them in the order listed.
Use a rice cooker. You can buy microwave-ready rice cookers that work perfectly for under $10, and you will have a perfect pot of rice in under 15 minutes. Regular dedicated rice cookers are perfect as well. Add some salt to the water for extra flavor.
Cut spinach into manageable strips or patches (the goal is to not have 6-inch strings after you cook).
Dice onions into ~1cm size pieces and slice mushrooms.
In a large frying pan or wok, put a teaspoon of oil in the bottom, along with garlic, ginger and any of the spices. Get this sizzling on medium heat, stirring constantly, to get the roots to start cooking and the oil to get nicely seasoned. Once you see signs of garlic or ginger starting to cook, add the mushrooms and onions to the pan and stir frequently. Once the vegetables are closer to cooked than raw (onions starting to caramelize, mushrooms starting to shrink noticeably), add spinach on top of the wok and let it wilt fully. A lot of water will come out of all these vegetables before they're done, and they will all lose volume as a result. The vegetables can be cooked to taste, but it's better for this dish to err on the side of undercooking.
If you're cooking in a flat pan, the water should mostly boil off. It helps to move all the vegetables to the side in a pile to let the liquid boil off more quickly. If you're cooking in a wok, it will tend to build up in the bottom. We haven't figured out a good way to avoid this water buildup (pre-steaming?), but the goal isn't to boil the vegetables, so you'll have to turn up the heat, stir a lot, or maybe risk losing flavor by pouring off some of this delicious whatever-it-is.
Scramble them. You don't need to add pepper or salt or anything but you can if you want to.
Put some rice in the bottom of a bowl. Put some of the other three components on top and add Lao Gan Ma to taste. Mixing thoroughly is recommended. The traditional ratios are 1:2:2:1 tofu:vegetables:rice:eggs, but of course you should do it differently if you prefer.
This should make about 4-5 solid bowls of Awesome Thing, but lab testing indicates that most people will want seconds, even if they don't really have room for more.
This dish is easy to customize -- just pick pretty much any green vegetable you like or have on hand (snow peas, green beans, broccoli) and add it to the big sautee. (Leafy things like kale work fine, but of course you have to prepare them like spinach.) You can add carrots if you cut them into very small strips or bits. If you want to add meat, _don't_ use it instead of tofu -- add it alongside. Crispy fried tofu is important for both texture and flavor. If you do want to add meat to this dish, we suggest grilled chicken strips with ample sichuan pepper or grilled beef strips with Chinese black bean/garlic sauce.