Halve, peel, and finely dice 1/2 cup onion. Mince the garlic. Peel and cut the potato into 1/2-inch cubes. Remove the stems and ribs from the kale and discard, then thinly slice. Pick the parsley leaves off the sprigs and finely chop the stems.

Heat 1 tablespoon olive oil in a pot over medium heat. Remove the chorizo from its casing, then add to the pot with the onion, parsley stems, and garlic and cook, breaking up the pieces. for about 5 minutes, until onions are softened and chorizo is cooked through.

Add the tomatoes and cook for about 5 minutes, until slightly thickened.

Add the potato, 4 cups water, and stock concentrate. Bring to a boil, reduce to a simmer, and simmer for about 15 minutes, until potatoes are fork tender. Season with salt and pepper. Add the shrimp and kale and simmer for about 3 minutes, until shrimp are pink and opaque in the center and kale has wilted.