In a small dish, mix together the cumin, salt, cinnamon, turmeric, chili powder, black pepper, cayenne, and clove powder. Set aside for now.
Heat a large pot over medium heat for 3 minutes. Add the sweet potatoes, onion, bell pepper, garlic, and ginger. Cook for about 3 minutes, stirring occasionally. Add a splash of water and stir if things start to stick.
Add the spices that you set aside earlier and toast for 1 minute, stirring constantly.
Add the tomatoes and peanut butter and stir until all the peanut butter is mixed in and any stuck bits of spices are loosened up from the bottom of the pot.
Add the water, stir and bring to a boil. Reduce the heat to low and simmer for 20 minutes, with a lid on the pot at an angle. Stir every 5 minutes or so with a wooden spoon, making sure you get up any stuck bits from the bottom of the pot.
Take off the lid, add the kale and simmer for an additional 10 minutes, with the lid off the pot, until the sweet potatoes are fork-tender.
Garnish with chopped peanuts and serve immediately or cool and store in the fridge. The stew will thicken and the flavors will continue to meld as it cools.