Heat the olive oil in a large pot over medium heat.
Add the onion and garlic and cook, stirring occasionally, until the onion is softened, about 5 minutes.
Add the cumin, coriander, turmeric, and cayenne pepper and cook, stirring, for 1 minute.
Add the vegetable broth and lentils and bring to a boil.
Reduce the heat to a simmer and cook, stirring occasionally, until the lentils are tender, about 20 minutes.
Remove from heat and stir in the cream and parsley.
Season with salt and pepper to taste.
Serve hot.