Start by preparing a workspace by laying a sheet of parchment paper onto a flat surface. (A baking sheet, cutting board, craft board or even the kitchen counter would all work perfectly for this project.)
3 Cups Powdered Sugar
Pour 1 cup of powdered sugar onto the parchment paper then use your hand to spread it out over the paper.
After that, add 4 extra large marshmallows to a medium to large size microwave-safe bowl then heat them in the microwave for 30 seconds. (The jumbo marshmallows will expand pretty quickly and will puff up rather big.)
12 Extra Large Marshmallows
Carefully remove the bowl from the microwave after 30 seconds, then spray your spatula with cooking spray and whip the melted marshmallows.
When the marshmallow consistency is smooth add food color and stir the mixture. If a deeper color is desired simply add a few more drops of food color and stir.
Red Food Color
Then pour the melted marshmallow onto the powder sugar. Use your hands or a spoon to scoop up the sugar and dump it onto the liquid marshmallow.
Finally, when the melted marshmallow is cool to the touch spray a layer of cooking spray on your hands then squish the marshmallow, glittery sprinkles (if using) and powdered sugar together to create easy fluffy slime.
Edible Glitter, Cooking Spray
Repeat the steps for other colors.
Blue Food Color