Prepare the peaches by pitting and peeling, then cut into small chunks. Measure out 2 cups of peach chunks into the blender.
Use a citrus juicer to extract fresh lemon juice and pour 1/2 cup into the blender with the peaches. Add honey if desired for extra sweetness.
Add 2 cups of ice cubes to the blender. Secure the lid tightly.
Blend on high speed until the mixture is smooth and icy, about 30-45 seconds. Observe the mixture turning from chunky to a thick, slushy consistency with no large ice pieces remaining.
Turn off the blender and check the texture. It should be cold, thick, and slightly syrupy, with visible bits of peach pieces still present. Serve immediately with a straw or spoon.