Make the meatballs

In a large bowl, combine the turkey, basil, green onions, garlic, fish sauce, cornstarch, sugar, kosher salt, and curry paste

Mix well, then with wet hands, form golf ball–size meatballs (about 2 tablespoons each) and set on a plate

You should have about 20 meatballs.Heat the vegetable oil in a large skillet over medium heat

Once the oil is glistening, working in batches, addthe meatballs in a single layer

Cook, undisturbed, until the meatballs are just browned on the bottom, about 3 minutes

Turn them carefully and cook to brown the opposite side, about 3 minutes

Transfer the meatballs back to the plate.Make the sauce

Drain off all but 1 tablespoon oil from the skillet and place over medium heat

Add the onion and cook, stirring occasionally, until softened, about 5 minutes

Add the garlic and cook until fragrant, about 1 more minute

Stir in the curry paste

Add the coconut milk and stir vigorously until the paste and milk are fully incorporated and the sauce is smooth

Add the lime juice, fish sauce, sugar, and fine salt

Taste and add more salt as needed.Increase the heat to high and bring to a boil, then return the meatballs to the sauce, discarding any collected juices

Reduce the heat to low, cover, and cook until the sauce has thickened and the meatballs are cooked through, about 20 minutes.Remove the skillet from the heat and stir in the fresh basil

Serve over rice or vegetables, garnished with basil and cilantro, if desired.