If using marshmallow root powder, combine 1 cup of warm water with the 1 marshmallow root and set aside for 5 minutes (or as long as overnight in the fridge).
Stir well and strain. Make sure that the liquid makes a whole cup.
Pour ½ cup of the prepared marshmallow root mix into the bowl of a stand mixer. Add the gelatin. Whisk slightly to incorporate and set aside. If not using marshmallow root simply pour ½ cup warm water into mixing bowl, add gelatin, and whisk slightly and set aside.
Pour the other ½ cup of water and 1 cup of honey, and cocoa powder if using, into a small saucepan and whisk to combine.
Slowly bring the water and honey mixture to a boil while stirring. If you have a kitchen thermometer (and I recommend it), you want it to reach at least 240°F. If you don't have a kitchen thermometer, just keep boiling, stirring constantly for 8 minutes.
Turn on mixer with water/gelatin mixture to medium speed and whisk while slowly pouring the honey/water mixture into the mixing bowl.
When add honey mix is added, turn the mixer to high and whisk for another 10-15 minutes or until it forms a stiff cream like the consistency of marshmallow cream. It should form soft peaks.
Add the probiotics and any flavor ingredients for the last 2 minutes of mixing.
Grease a 9x13 inch baking dish with coconut oil or line with parchment paper, leaving some on the sides to be able to pull up.
When marshmallows are whipped, pour into the lined/greased dish and smooth evenly.
Let rest at least 4 hours (overnight is better).
Flip onto a cutting board and cut with a well-oiled pizza cutter or knife.
Store in an airtight container on the counter.
Do NOT store in the refrigerator as they will melt. Store in an airtight container at room temperature. The probiotics will decrease the shelf life to 3-4 days. Without the probiotics, these will last 2-3 weeks on the counter.