These beans came to Liguria from Spain in the 17th century, and found an ideal environment in the Nervia valley, the Impero valley and the Argentina valley. Natural selection has produced three different types of beans, grown in three small municipalities: Badalucco, Conio and Pigna.
The ideal areas for their cultivation are those at the highest points, where the soils are well drained and the spring water is chalky and rich in mineral salts.
The differences between the three types can be seen mainly in their shape and size, due to the different soils, water and microclimates: kidney-shaped and slightly larger the Conio legume; egg-shaped and smaller those of Badalucco (where they are called 'rundin') and Pigna. They all have the a soft, delicate consistency in common.
The best way to enjoy them is to boil them and season them with a drizzle of extra virgin olive oil: after soaking overnight, they are boiled in water with garlic, bay leaves, a few tablespoons of oil, and a little salt is added at the end. The beans should be soft but firm, without breaking down, for an even tactile sensation on the tongue, as if there were no skin.