Preheat dutch oven or heavy bottom medium pot on low-medium heat and swirl oil to coat.
Add onion and garlic, cook until golden brown (5 minutes), stirring occasionally.
Add turmeric, coriander, curry powder, cumin and salt; cook for another 30 seconds, stirring frequently.
Add coconut milk, tomato paste, water, lentils and stir to combine.
Bring to a boil, cover and cook on low for 45 minutes.
Remove from heat and let stand 5 minutes.
Add cilantro and/or green onions and stir.
Adjust thickness of curry with more broth, if you wish.
Serve hot garnished with more cilantro or green onions, lime, avocado and yogurt, if you wish.
