Really, I pretty much gave you the recipe in the title of the post! Here's a vegan "milk" shake healthy enough to have for breakfast (which I just did). Sorry I didn't take a photo. I tasted it to see if it was good, and then it was gone before I could photograph it: Yes, it was good!
1 ripe banana, peeled
1 - 2 T. creamy peanut butter, to taste
chocolate soymilk or almond milk
Wrap the peeled banana in plastic wrap and freeze overnight.
The next day, unwrap the banana and cut into 1-inch chunks. Add the banana, peanut butter, and about 1/2 c. of the soymilk or almond milk to the jar of a blender. Start blending, then add soymilk as necessary to get the desired consistency. Pour into a glass, and enjoy!