Heat oil: In a large pot, heat the vegetable oil over medium heat until the oil shimmers. Add in red pepper flakes (if using) and allow to bloom for about 30 seconds.
Sauté aromatics: Add the diced onion, minced garlic, grated ginger, diced jalapeño. Cook for 3-5 minutes, or until the onions are translucent, and starting to take on a little color.
Add spices: Add in the paprika, ground cumin, and ground coriander. Stir to coat the aromatics and cook for about a minute, stirring constantly, to toast out the raw flavor of the spices. Add a splash of water as needed to keep things from sticking.
Add ingredients: Add in the crushed tomatoes, 1/2 cup peanut butter, 2-3 cups vegetable broth, and 1/2 teaspoon kosher salt. Stir to combine everything, doing your best to break up any big lumps of peanut butter into the broth. Then add in the red bell pepper, cubed sweet potato, and drained chickpeas. Stir to combine.
Simmer: Bring the mixture to a boil, then reduce the heat to low to establish a simmer. Allow to simmer, covered, for about 10 minutes. Stir occasionally to prevent sticking.
Add the greens: Add the sliced collard greens to the pot. Stir them in, then put the lid back on and simmer for another 10-15 minutes, or until the sweet potatoes are very tender. Stir occasionally to prevent sticking.Note: I add the collard greens now because I prefer them to be very tender. If you'd like to keep them a little fresher, feel free to add them later. If you are substituting in a more tender green such as baby spinach or baby kale, you can add them later as they only require about 3-5 minutes of cook time. Adjust seasoning: Once the sweet potatoes are tender, taste the stew and adjust the seasoning with more salt as needed. (Exact amount will depend on the salt content of your broth, tomatoes, chickpeas, peanut butter, etc.)
Serve: Ladle the stew into bowls and enjoy! You can garnish with extra red pepper flakes, fresh chopped cilantro, roasted peanuts, and a squeeze of fresh lime juice to brighten everything up.