• Combine rhubarb and strawberries in a pot with 1/4 cup water and cook until soft, 8–12 minutes. If using frozen fruit, you may need to simmer a few extra minutes after the fruit softens to evaporate excess liquid.
• Remove from heat, puree until smooth with blender and let cool.
• Combine with remainder of ingredients. Check the consistency of the puree. If it pours like a smoothie or spreads on its own when spooned onto the tray, return it to the pot and simmer a few minutes longer to evaporate excess liquid. The puree should be about the consistency of thick applesauce—thick enough to stay where you spoon it and require a spatula to spread evenly.
• Spread the puree evenly onto silicone-lined dehydrator tray (or parchment lined baking sheet for oven), about 1/8 up to 1/4 inch (3–6 mm) thick. Keep the layer as even as possible so it dries uniformly.
• Place in dehydrator and dry at 135°F (57°C) for 8-10 hours.
• Press leather with flat fingers, if there’s an indentation or any dark, wet spots, it’s not ready. If it comes off easily, it is done. Watch how to tell if Fruit Leather is Dry on YouTube.
• Roll and cut into strips. Let cool completely then store in sealed container for up to 1 month or in the freezer for longer.
• Makes 2-3 cups puree for an 8x6 inch to 8x8 inch sheet of leather

Oven Drying

• For oven drying: Line a baking sheet with parchment paper. Spread the puree evenly and rotate the pan as needed for even drying. If the edges dry before the centre, trim off the finished pieces and continue drying the remaining fruit leather until no sticky spots remain. Turn to 170° F (70°C). Dry for 6-8 hours. (see post for details)