Spray an 8x8 inch metal baking dish with non-stick spray. Line with parchment paper and spray parchment paper with non-stick spray. Set aside.
Pour 1/2 cup of water into the bowl of a stand mixer fit with a whisk attachment. Sprinkle gelatin powder and turmeric over water and mix lightly with a fork. Place bowl onto stand mixer and set aside.
Pour remaining 1/2 cup of water into a large sauce pan with high sides. Set over medium low heat. Add honey and salt to the pan and stir gently. Heat mixture until it registers at 240°F on a candy thermometer. This process will take anywhere from 8 minutes to 11 minutes depending on your stove top. Watch mixture closely as it heats up to monitor temperature and to avoid bubbling over.
When the honey mixture reaches 240°F, remove from heat. Working quickly, turn mixer on low and stream hot honey mixture into the bowl. Mix on low for several minutes until mixture cools slightly. Increase speed gradually until eventually it reaches high. Mix until marshmallow mixture is light and fluffy and has soft peaks. Be cautious to not over mix to the point that the marshmallow mixture becomes too stiff to spread. Spread marshmallow mixture into prepared pan.
Allow marshmallow to set uncovered for at least 4 hours or overnight. Use a pizza cutter or sharp knife to cut marshmallows into 1 inch squares. Sprinkle marshmallows with tapioca starch to keep them from sticking, if desired.