Place all of the ingredients in your blender. Blend until everything is smooth. Taste and add the sweetener if needed (I found I didn't need any, as my banana and raspberries were ripe enough).

Pour into popsicle molds and allow to freeze completely, 6 hours to overnight.

When you're ready to serve, run warm water over the popsicle mold, until you can slide the popsicle out.

Makes around 6 popsicles, depending on the size of your molds.