Preheat the oven to 450°F-500°F/ 230°C-260°C. Cover a baking sheet with parchment paper; set aside.
Trim the tough bottom stem from the cauliflower, leaving the head and leaves that are close to the stem intact.
Place the cauliflower, white side down, in a large pot and add one tablespoon of salt. Add enough water to cover the cauliflower completely. Cover with a lid and bring to a boil on medium-high heat. Reduce heat to medium and boil for 8-12 minutes or until fork tender.
Take the cauliflower out of the water and let it cool down to room temperature.
Place the cauliflower on the prepared baking sheet.
Rub 1-2 tablespoons of olive oil between your hands, then massage the cauliflower to apply a thin and even layer.
Season with garlic powder, salt, and pepper.
Bake in preheated oven for 20-25 minutes or until browned around the edges.
Remove from oven, and carefully rub with one tablespoon of olive oil.
Season more if needed, and serve hot or at room temperature.