Prepare the sweet potato by slicing the potato lengthwise like toast about 1/4 inch thick. Preheat the oven to 425°F. Place the potato toast on a lined-baking sheet. Cook for 25 to 30 minutes.
In the meantime, wash the lentils by rinsing them in a colander. Place the washed lentils in a large pot. Add water. Let the water come to a boil while on high then reduce heat to low and cook the lentils on simmer for 25 minutes.
Add the vegetables, spices and continue to simmer for another 10 minutes until vegetables are soft.
Add the kale and let it wilt about 5 minutes.
Using an immersion blender blend the soup to anywhere between chunky to smooth. Adjust the seasoning.