Lavender Dishwashing Soap 2 Cups soap flakes 1 gallon water 25 drops of lavender essential oil Place soap flakes and water into a pan. Heat over medium heat stirring occasionally until it boils and until soap dissolves. Lower heat and simmer for 10 minutes to thoroughly combine the ingredients. Remove from heat and let liquid partially cool, add the essential oil and stir. Pour into a clean plastic squeeze bottle or re-used dish soap bottle.