Mix baking soda, citric acid and cornstarch in a bowl. Sieve this mixture so that no lumps are formed.
Meanwhile, melt the coconut oil in a saucepan or in the microwave.
Gently stir it into the mixture with a spoon until you get a creamy mixture.
Caution: The mixture must not come into contact with water, otherwise it will immediately start to bubble. So make sure your hands and work utensils are dry.
Finally, stir in the fragrance oil. And if you want dried flowers.
Press the bath ball mass into the molds very firmly with your fingers. Press the molds firmly together and let them rest for 2 hours. I always put them in the refrigerator for half an hour afterwards, so that the coconut oil becomes really firm.
Take the bath bombs very carefully out of the mold and then let them stand for another 2 hours.