Heat olive oil in a large skillet over medium-high heat. Add onion and garlic and cook until onions are soft and translucent, about 5 minutes. Add curry powder and pan-fry in the hot oil for 2 to 3 minutes. Pour in coconut milk and stir to combine. Add cauliflower florets, coating them in the sauce.
Cover, reduce heat, and simmer over low heat until cauliflower reaches desired softness, about 30 minutes. Top with a sprinkle of saffron and serve with basmati rice.