Generally cannellini beans and great northern beans are considered to be interchangeable in many recipes. However, they are different. Cannellini beans are larger in size and shaped like a kidney bean. They have a mild earthiness and slightly nutty flavor. Cannellini beans have a thicker skin which results in a creamy texture after cooking. Great northern beans are slightly smaller than cannellini beans, and have a thinner skin, resulting in a slightly less creamy texture after cooking.