This is one I got from T.V. and it is the easiest, tastiest and moistest cake I have ever made. And with yoghurt .... why, it is nearly health food!
Start off with a whisk for all the wet ingredients, then fold in dry with a spatula. Avoid overworking the flour as that will toughen the cake. I sometimes swirl good quality home-made lemon curd through the batter [NOT shop bought]