Meanwhile, heat remaining 2 tbs oil in a deep frypan over high heat. Add onion and cook, stirring for 2 minutes or until soft. Add garlic, ginger, turmeric and lentils. Cook, stirring, for 1 minute or until combined. Add stock and half the coconut milk. Simmer, stirring occasionally, for 9-10 minutes until lentils are just cooked. Then fold through remaining coconut milk.