To make the yarrow tea place 1⁄4 cup dried yarrow (or 1⁄2 cup fresh yarrow) in a jar, pour 1 cup simmering water over. Steep 30 minutes to 1 hour, strain and then chill completely before using in recipe.

Put on protective clothing, eyewear and gloves before carefully stirring lye into the yarrow tea until dissolved. Set the solution aside to cool to between 100 and 110 degrees.

While the lye solution cools, gently warm the oils to around 100 to 110 degrees so that the two mixtures are close in temperature.

When both solutions are between 100 and 110 degrees. Pour the cooled lye solution into the warmed oils. Use an immersion blender to stir the batter until it thickens or achieves "trace." This is when soap dripped back into the pot leaves a visible "trace" on the surface.

Blend the witch hazel into the soap once you reach light trace. Be sure that it’s blended in well, to avoid separation.

Pour the soap batter into a prepared mold and cure the soap for a few days until it can be easily removed from the mold. Slice the soap and cure for about 4 weeks to allow extra moisture to evaporate out before using.