Preheat oven to 425°F. Place cauliflower in a food processor. Cover and pulse several times until cauliflower is evenly chopped into rice-size pieces. (If necessary, process cauliflower in batches.) Transfer cauliflower to a foil-lined 15x10-inch baking pan. Drizzle with 1 tablespoon of the oil and sprinkle with 1/4 teaspoon of the salt; toss to coat. Spread cauliflower in an even layer in the pan. Roast, uncovered, 23 to 25 minutes or until lightly charred, stirring once.