Best protien supplement to put in smoothies?

What is the best protien supplement to put in a smoothie? I am not big on protein drinks but I like green shakes so I thought I could find a good protein to add to my shakes that won't make it taste funny. Didn't know whether to go with soy or whey... let me know what you think please.
Thanks!

Try unjury unflavored.

Thanks,  I will.

What kind of blender do you use for your green smoothies?  I have the Nutri Bullet and I can not handle all the foam!