Paella is precious in Valencia, Spain. Food writer Matt Goulding asserts that you can find the entire history of Spain within the perimeter of the paella pan. The key to the dish is the rice and saffron. Goulding explains the ideal rice varieties behind the dish and how it was conceived in the orange fields of Valencia, using ingredients available and cooked over a fire in a flat, open pan. His book “Grape, Olive, Pig” focuses on the food culture of Spain.