To clean haw fruit, first remove any stems or leaves. Soak them in water for a few minutes, shaking them around to remove any dirt on the surface. Drain. Remove the top and bottom ends of each haw and slice it open to remove the pit.
Once all the hawberries been sliced and pitted, add them to a saucepan along with 1 cup of water. Cover the saucepan with a lid and set it on medium heat.
Once the water starts to simmer, continue to cook the fruit for 2 minutes. Then remove from heat and splash in another 1/2 cup of water to cool it down slightly.
Add the softened haws and water, along with 1/2 cup of sugar, to a blender. Blend until smooth (see Note 2).
Spread the mixture evenly over a half-sheet pan (or two quarter-sheet pans). If your pan is not non-stick, line it with parchment paper or wax paper first.
Use a dehydrator, or your oven set to the lowest temperature, to dry the sheets until they are slightly tacky. They should not feel moist or squishy to the touch. With my oven set to 170 °F, it took 6 hours.
Once the haw leather is dried, and while it’s still warm, gently pull the sheet by the corners to peel it off the pan. Roll into a tight log and secure with plastic wrap.
Let rest for 1 hour before unwrapping and slicing. (It helps to dip your knife in water between cuts to prevent the haw candy from sticking to the blade.)