Step 1 Spray a large frying pan or wok with oil and place over high heat. Add chicken, in batches, and cook for 2–3 minutes, until golden. Remove and set aside.
Step 2 Spray pan with a little more oil. Add onion and cook, stirring occasionally, for 3–4 minutes, until golden. Add curry paste; cook, stirring, for a further 1–2 minutes, until fragrant. Add tomatoes, stock and pumpkin. Bring to the boil, cover, reduce heat to low and simmer for 15 minutes, or until pumpkin is tender.
Step 3 Return chicken to pan with zucchini. Simmer for a further 3 minutes, or until chicken is cooked through. Remove from heat, add brown sugar and lime juice to taste. Serve with steamed basmati rice and garnish with lime wedges and coriander.