Oct 26, 2020 · Watch on. Recipe: 2 1/2 Cup Baking Soda. 1 Cup Citric Acid. 60g Menthol Crystals ** (30g if 60g is too strong for you) 2 tbsp Coconut Oil (Helps bind the shower steamer, but it is not necessary or another oil can be used) 2 tsp Essential Oil. **Dissolve Menthol Crystals in Rubbing Alcohol First. 2" Square mold used is available on our website .... "/>