1 large bunch sweet potato greens
1 tablespoon vegetable oil
2 shallots, minced
1 clove garlic, minced
1 teaspoon minced fresh ginger root (from a 1/2-inch piece)
2 teaspoons grated fresh turmeric root, or 1 teaspoon ground turmeric
1 red thai chili, finely sliced
2-inch lemon grass stalk, trimmed and finely sliced
1 to 2 teaspoons soy sauce, or to taste
1 cup coconut cream plus 1 cup water (or substitute 2 cups light or regular coconut milk)
2 to 3 teaspoons raw or brown sugar, or to taste
Salt and pepper, to taste
Bring a large pot of water to a rolling boil. Trim off any thick stems from greens. Add to boiling water and blanch for 60 seconds, then immediately transfer greens to a bowl filled with ice water to stop the cooking. Drain.
Heat oil in a large pan or wok over medium heat. Add shallots, garlic, ginger, turmeric, chili, and lemongrass and stir until fragrant, 1 to 2 minutes. Stir in soy sauce.
Add coconut cream and water (or coconut milk) and bring to a simmer. Add blanched greens and return to a boil; reduce heat to low and simmer for 2 minutes. Add sugar and season with salt and pepper to taste. Spoon into bowls and serve with rice.