Savory Grits with Slow Cooked Greens

To make the greens: Put about 12 cups of water in a large pot and bring to a boil over high heat. Add 1 tablespoon of the salt, then add the greens and cook uncovered until softened, about 10 minutes. Drain well, pressing the greens to extract as much liquid as possible. When cool enough to handle, transfer to a cutting board and chop finely.
Warm the oil in a medium sauté pan over medium heat. Add garlic, ginger, chili powder, cayenne, and the remaining 1/4 teaspoon salt. Saute for 2 minutes. Stir in the greens and stock and bring to a simmer. Decrease the heat to medium-low, cover, and simmer, stirring occasionally, until the greens are tender, about 45 minutes. Stir in the bell pepper and jalapeño. Increase the heat to medium-high, cover, and simmer for 2 minutes. Taste and season with more salt if desired.
While the greens are simmering, make the grits: Put 3 cups of the stock and the salt in a medium saucepan and bring to a boil over high heat. Slowly pour in the grits, whisking constantly until no lumps remain. Return to a boil, then immediately decrease the heat to low. Simmer uncovered, whisking occasionally to prevent sticking, until the grits have absorbed most of the liquid and are beginning to thicken, 3 to 5 minutes. Add the remaining 1 cup stock and simmer for 10 minutes, whisking occasionally, until most of the liquid has been absorbed. In a blender or food processor, make cashew cream by combining cashews and water and blending until smooth. Stir in the cashew cream, cover, and simmer, whisking frequently, until the grits are soft and fluffy, about 30 minutes.
Add the parsley and whisk well. The grits should be firm and creamy. Add a bit of water to thin them if necessary.
To serve, top the grits with the greens, using a slotted spoon so that the liquid drains from the greens. Add a splash of hot-pepper vinegar and season with black pepper.