Preheat the oven to 230°C.
Place a piece of parchment paper on the bottom rack of the oven. Wash and pierce the sweet potato a few times then place on the top rack. Bake for 1 hour or until soft. Set aside until cool enough to handle.
In a large pot, warm 1 tablespoon oil over medium heat. Add the onion and cook for 2-3 minutes. Then add the garlic, pepper, curry powder, cumin, turmeric, and salt, and continue to cook for 5 more minutes.
Add the rinsed lentils, diced tomatoes, tomato paste, and vegetable broth. Bring to a boil, reduce to a simmer and cook for 15-20 minutes, just until lentils are tender. Turn heat to low, stir in peas and coconut milk then cook until heated through.
Once the sweet potato is cool enough to handle, slice down the center and scoop the filling out into a measuring cup. Add 1 cup of the flesh to the pot and stir to combine.
Serve with cashew cream and coriander