Yes there is!
You gain fat easily, but you also gain muscle easily. In fact, you probably have some mass already.
As for endomorphs, are you talking about bodybuilders? I don't know of any recent bodybuilders, but if you look like classic ones like Boyer Coe or Lou Ferrigno, or Franco Columbu, you'll see that they can get the most mass. With the larger joints, they might not be as shapely as the Frank Zanes, but Frank looked better by himself. Beside the big guys, he looked small.
You need to to high reps and lots of cardio. Eat well, without restricting the calories too much (or you'll yo yo). There is no reason why an ectomorph can't have a great body.