You might want to do 2 scoops, 1-2 bananas, a high glycemic carb source, in skim milk. Strawberries optional. I try to cut out any fat from a PWO shake, so go with skim milk not half and half. Unless this is a weight gaining shake and not for PWO in which case half/half is fine. Also if it's weight gainer I'd add some natural peanut butter and some oats. DELICOUS.
But you definitely need a carb source besides the banana. The banana is going to re-fill your liver glycogen stores, but you need some type of sugar for your muscle glycogen stores to be replenished (I think?) You can do malt/dex, but I just use sonoran desert honey, cause its delicious and I like the flavor better than regular sugar tasting stuff...but it might be more expensive. Never tried malt/dex in a shake.