Heat the oil in a saucepan over medium heat, add the cumin seeds, garlic and ginger and cook for 1 minute. Add the lentils and cook for a further minute.
Add the stock to the pan, stir and simmer for 25 minutes, until all the liquid is absorbed and the lentils are tender. Check the seasoning. Remove the pan from the heat and set aside to cool. Stir in the mint and coriander and add a squeeze of lime.
Arrange the spinach leaves in individual bowls, top with a quarter of the lentils and the goats' cheese and serve sprinkled with black pepper.