In a small bowl, beat together the peanut butter and Greek yogurt until light and fluffy, about 2 minutes.
Lightly spray an ice cube tray with oil based cooking spray. Place a small piece of training treats or kibble into each opening in the ice cube tray.
Fill the ice cube tray with the peanut butter mixture. Press the mixture into the cubes with the back of your spoon. Use a paper towel to smooth out the top of the peanut butter.
Press a milk bone into the center of each cube, about half way down. Freeze until solid, about 6-8 hours.
Leave the pupsicles out for about 5 minutes prior to serving. "Crack" the ice cube track as you would to remove ice and then pull out the individual 'pupsicles.'
Serve your dog the pupsicle outside or on an easy-to-clean surface. Hold the pupsicle by the 'stick' - or give them the whole pupsicle - and let your dog lick away. Good dog!