Heat a 6-qt. sauce pot over medium high heat.
Add in olive oil and coat the pan. Add in onions, cayenne pepper, cumin, coriander, star anise, cinnamon stick and bay leaf. Sweat onions until translucent.
Add in garlic, ginger and lentils. Stir lentils to coat with mixture. Add in cold vegetable stock. Bring to a boil, reduce heat and simmer for 15 minutes.
Add in the sweet potatoes, chopped tomatoes, peppers and dates. Stir into mix and allow to cook for another 25 minutes or until the sweet potatoes are soft.
If tagine gets too thick, adjust consistency with vegetable stock or cold water. Adjust seasoning with salt and pepper.
Garnish with fresh parsley or coriander for service.