I use this before and after the gym, it's a good balance of carbs, proteins and fats...
1 scoop whey protein
2 tsp peanut butter
1 small yoghurt
water, vary amount depending on how thick you like it
It's not built for flavour, but nutrition. It has a macro nutrient ratio of 50:30:20, carbs:proteins:fats, which is best for most workout routines. Having said that as long as you get a good combination of the flavour of the yoghurt and the flavour of the whey protein it can taste pretty good.