
Fill a pot with the water and sprinkle the agar agar over the top. Whisk together and turn on the heat to medium-high. Whisk continuously until the agar agar is bubbling and thickening, then stir in the sugar. Continue to stir until the sugar is completely dissolved.
Turn off the heat and whisk in the red food coloring, citric acid, and candy flavoring.
Pour the liquid into a shallow glass pan so that the liquid is at least 1-2 inches deep. Let the liquid set at room temperature for 2-3 hours or in the fridge for 1 hour or until fully hardened.
Use your fingers or a butter knife to loosen the solidified block from the container. Flip the container onto a cutting board or plate. For a more natural look, tear the block into pieces; for a cut-stone look, use a knife.
For a long dry, leave the candies uncovered at room temperature for 7-10 days. For a quick dry, use a dehydrator at 95°F for 72 hours.
Serve the candies at room temperature. Store in an airtight container for up to 2 weeks.