Pour your root beer into a cup and leave uncovered in the refrigerator for at least 2 hours. This is to remove some of the carbonation which will create air bubbles in our popsicles, leaving them crumbly. If you have some carbonation left, that is okay
Evenly divide the ice cream among your popsicle molds. Top with the root beer and gently stir a little. Much of the ice cream will float back to the top, but you should still have plenty throughout to give the root beer a touch of creaminess.
Freeze for at least 4 hours, preferably overnight.
Gently pull out the popsicles from the molds and keep frozen in an airtight container.