Break up your cauliflower into small florets using a chef knife to cut away the core. Place all florets in a large bowl and add the oil, salt, pepper, and garlic powder. Toss well.
Lay the florets (non-touching) on a foil lined baking tray and place in an oven preheated to 225°C or about 420°F. Roast for 20 minutes or until you see some blackening due to caramelization. Remove and serve immediately.