Potatoes and Peas in a Yoghurt Sauce

I'm a little puzzled by this dish. It was tasty enough, but very soupy. Twelve ounces of potatoes and a cup of peas were swimming in 2/3 cup water plus 1-1/4 cups yoghurt plus another 1-1/4 cups water. (It is typical of the way recipes are written in Jaffrey's books that water is added in the instructions, but it's not listed in the ingredients. I find this rather annoying.) Of course the besan thickened the sauce a bit, but there was still much more sauce than I expected.

This was a good side dish (in an American-style Indian meal), and I expect it would make a nice vegetarian main course, served over rice.