Place peanut butter in the bottom of blender (this helps make sure it's fully incorporated)

Add bananas

Blend on high for several minutes

Scrape down sides & continue blending until creamy

Transfer to medium size bowl & fold in jelly/jam being careful to not fully blend it in. You want ribbons of jelly throughout.

Enjoy immediately for a soft serve ice cream or transfer to air tight container & freeze overnight for firm ice cream.