Preheat your oven to 170°F (77°C) and line a baking sheet with parchment paper. If your oven doesn’t reach as low as 170°F, an oven-style air fryer with a dehydrate setting can be used as an alternative.

Place the cleaned and hulled strawberries into a blender, add the juice of half a lemon, and if you’re using it, a keto-friendly sweetener.

Blend the ingredients together until you have a smooth puree with no remaining chunks of fruit.

(Optional Step - Boiling): Transfer the puree into a saucepan and bring it to a boil over medium heat, allowing it to boil for 10 minutes; this helps to concentrate the flavors and will reduce the baking time. If you choose to skip boiling, the baking time will increase to 6-7 hours instead of 3-4 hours.

After boiling (or skipping), pour the strawberry puree onto the prepared baking sheet, and use a spatula to spread it out evenly to about ⅛ inch thickness.

Bake the spread puree in the preheated oven for 3-4 hours (or 6-7 hours if skipping the boiling step), or until it is dry to the touch and no longer sticky. Monitor the oven to ensure it doesn’t over-dry or burn.

Once the fruit leather is done baking, remove the tray from the oven and let it cool completely on the parchment paper.

When the fruit leather has cooled, gently peel it off the parchment paper. If it's sticking, placing another piece of parchment on top and flipping it over may help to peel it off more easily.

Cut the fruit leather into strips with a sharp knife or scissors, then roll them up from one end to form the roll-ups.

Store the finished fruit roll-ups in an airtight container. They can be kept at room temperature for several days or stored in the refrigerator for longer periods.