In a small saucepan cook the onion and garlic in 1 tablespoon of the oil over moderately low heat, stirring, until the onion is soft. Add the wine and simmer the mixture until the wine is reduced by half. Add the parsley, basil, 1/2 cup of the beans and the chicken broth, simmer the mixture stirring for 1 minute, and in a blender puree it. In the saucepan stir together the puree, the remaining 1/2 cup beans, and salt and pepper to taste and simmer the mixture for 2 minutes.
In a skillet, preferably non-stick, heat the remaining 1 tablespoon oil over moderately high heat until it is hot but not smoking and in it saute the shrimp, seasoned with salt and pepper, for 1-1/2 to 2 minutes on each side or until they are cooked through. Transfer the shrimp with a slotted spoon to a plate and keep them warm. To the skillet add the scallops and saute them, stirring, for 1 to 2 minutes, or until they are cooked through. Divide the bean sauce between 2 shallow bowls and arrange the shellfish over it.