Curry paste can be found in the Asian aisle of most supermarkets.
Heat olive oil in a large saute pan over medium heat. Saute onion and ginger until softened, then add garlic and continue cooking until fragrant. Add cauliflower and saute another 5 minutes. Stir in coconut milk, curry paste and salt. Cover and simmer 15 minutes to allow flavors to infuse and the cauliflower to soften.