Preheat the oven to 425 degrees F.
Place the cauliflower on a nonstick baking sheet and spritz it with olive oil. Sprinkle it with a pinch of salt freshly ground pepper. Roast the cauliflower for 15 minutes, until just slightly crisp.
While the cauliflower is roasting, whisk together the soy sauce, hoisin, sherry vinegar, sesame oil, brown sugar, cornstarch, garlic and ginger. You may need to whisk a few times to get rid of any cornstarch lumps.
After 15 minutes, pull the cauliflower out. Add the chiles and pour the sauce all over the cauliflower. Toss well to coat all the cauliflower. Return the pan to the oven. Roast for another 15 to 20 minutes, stirring and tossing the cauliflower ever 5 to 10 minutes. This will depend on your oven - you just don’t want the sauce to burn in the corners, but you want to give it enough time to thicken up between tossings.
When the cauliflower is roasted and sauce, remove the pan from the oven. Cover it with the green onions and peanuts. Serve immediately as a side or on top of jasmine rice!