Prepare the cassava leaves by washing well, removing tough stems and veins, then finely chopping or pulsing in a food processor; set aside.
In a dry skillet, roast the peanuts over medium heat, stirring, until golden-brown and aromatic; let cool.
Grind the cooled roasted peanuts in a food processor or mortar and pestle until they reach a thick, nearly peanut-butter consistency; reserve.
Heat the cooking oil in a large skillet or pot over medium heat and sauté the chopped onion until softened, about 4–5 minutes.
Add the shrimp to the pan and cook gently for 2–3 minutes until they start to turn opaque.
Pour in the coconut milk, then add the minced garlic and crushed red pepper; bring to a gentle simmer for a few minutes to combine flavors.
Stir in the ground peanut mixture until it dissolves into the sauce and begins to thicken.
Add the chopped cassava leaves, mix thoroughly into the sauce, then reduce heat to low and simmer, uncovered, for 1 to 1½ hours, stirring often, until the leaves are fully cooked and the sauce has thickened.
Taste and season with salt as needed, then remove from heat and serve hot with boiled rice or xima if desired.
