Preheat oven to 400 degrees F. Cut cauliflower into florets; toss with the olive oil, garam masala, 1/4 tsp. kosher salt, and 1/4 tsp. black pepper. Spread in a 15101-inch baking pan. Stir in almonds. Roast 25 to 30 minutes or until lightly brown and tender, stirring once. Remove pan from oven. Stir in raisins. Cool slightly.
Meanwhile, cook basmati rice according to package directions. Serve cauliflower mixture over rice. Drizzle with additional extra-virgin olive oil and chutney, if desired. Add mint just before serving.