How to make Harry Potter inspired bath bombs
In a large bowl, combine baking soda, citric acid, cornstarch and Epsom salt. Separate mixture into two bowls.
Combine grapeseed oil, water and fragrance in a small cup.
Add cosmetic mica powder to each dry mixture bowl. Start at about ½ tsp and increase until desired color is reached. Note: the mixture will darken once the liquid is added.
Evenly divide liquid into each bowl while stirring to avoid activating the bath bomb mixture.
Layer the mix into the mold and firmly press together. Dry overnight before removing from molds.
Wrap or store in a dry, cool place.