I've been trying to gain weight for a whole now, so what I've been doing was I got a ton of sandwich bags and sliced up whatever fruits I could get my hands on (bananas, tangerines, etc) and stuck them in there and put in some frozen yogurt and mixed the whole bag with protein powder and left them in the freezer. It tastes just like an ice cream smoothie, plus it's super good for you. I still have some of these left in the freezer so I'll attach a photo later.