Lightly coat an 8x8 pan with cooking spray. Line the pan with parchment paper and lightly coat the parchment with cooking spray. Set aside.
Pour ¼ cup water into the bowl of a stand mixer. Sprinkle the gelatin over the surface of the water and leave the mixture to set without touching it for 10 minutes while you move on to step 3.
Add sugar, honey, and remaining ½ cup water to a medium saucepan. Cook over medium heat, stirring until the sugar dissolves. Bring the mixture to a simmer and cook without stirring until a candy thermometer reads 240°F, about 12-15 minutes.
Pour the sugar mixture into the gelatin mixture and beat on low speed until combined. Once combined, increase speed to high (being careful not to cause any of the hot mixture to splash out of the mixer) and beat until the mixture becomes thick and fluffy and triples in volume, about 8-10 minutes. Add the bourbon and beat the mixture until combined.
Lightly coat a spatula with cooking spray and use it to scrape the marshmallow mixture into the prepared pan. Spread the mixture so it fills the pan and smooth the top of the mixture (it’s okay if it isn’t totally even). Cover the pan with plastic wrap and let the marshmallow set for 1 hour.
Once set, remove marshmallow from pan and peel away parchment paper. Lightly coat a carving knife or chef’s knife with non-stick spray and cut the large marshmallow square into 8 rows and 8 columns to create 64 squares.
In a small bowl, whisk together confectioners sugar and cornstarch. Dip each marshmallow square into the bowl and gently coat each side with the sugar mixture, tapping off any excess.