Steps 1-4: In a large mixing bowl, add the baking soda, buttermilk and cornstarch. Whisk dry ingredients together.
Step 5: Add the coconut oil. This binds all the ingredients together, so you bath bombs don’t crumble when you touch them!
Steps 6-7: Add orange essential oil, Gran Marnier and orange color. Start with 1-2 drops of color and mix it in. If you want a darker color, add 1-2 more drops and repeat until you get the color you want.
Step 8: Mix ingredients thoroughly. You may need to use your hands to break down any lumps and make sure everything is mixed in. The mixture is perfect when it holds together when you press it into your hands and feels like wet sand.
Step 9: Mix in the dried orange peel.
Steps 10-13: Fill both sides of the mold with the mixture, press molds together and grind to remove excess mixture. Gently tap each side of the mold to release the bombs. To avoid the bombs breaking during the drying phase, I put them in a mini muffin tin. They fit perfectly!
Allow to dry a minimum of 24 hours. If your climate is wet or cold, allow an additional 24 hours. My rule of thumb is that when it is hard to the touch, they are ready for the tub! Store in an airtight container until ready for use.