Preheat oven to 325° F. Line a baking sheet with parchment paper.
Cut bananas lengthwise and lay on baking sheet.
Bake for about 10 minutes or until golden brown. Allow to cool for a few minutes.
Blend roasted bananas for a couple minutes until smooth. Add water a couple tablespoons at a time until you reach your desired consistency. If desired, add a splash of lemon juice to keep puree from browning. This is optional.
Portion out puree into air tight containers or freeze in silicone trays. Store in fridge for up to four days or freezer for up to three months.