Heat coconut oil in a large pot over medium heat. Add onion, garlic, and ginger. Cook until onions are translucent and the mixture is fragrant.
Stir in turmeric, curry powder, cumin, and cayenne pepper. Cook for about 1 minute, or until spices are well combined and aromatic.
Bring the mixture to a boil, then reduce heat and simmer for 20 minutes, or until lentils are tender and the curry has thickened.