Step 1 Combine olive oil, onion, spices, chilli, garlic, ginger and coriander stems in a small food processor. Blend to a paste (add a little water to reach a thinner consistency if required).
Step 2 Spray a heavy-based pot with oil and cook paste for around 5–10 minutes over low heat, stirring often. If mixture starts to catch or burn, turn down heat and add a little water.
Step 3 Add tomatoes, increase heat and simmer, stirring occasionally, for 10–15 minutes or until the liquid looks thick rather than watery. Add coconut milk, stock, 1/2 cup water, snow peas and prawns. Allow to simmer very gently for 4–5 minutes, or until prawns are just cooked. Stir in the chickpeas.
Step 4 Serve curry on rice topped with coriander leaves.