This cleaner is liquid enough to pour from a squeeze bottle and works well when you need something a bit stronger than soap and water.
6g castile bar soap, unscented
1 cup (250ml) water
30g (2TB) washing soda
Essential oils (optional)
Finely grate the bar soap or chop it into small pieces. If you don’t have a scale 6g is about 1.5TB when grated (a baking not eating tablespoon measure) or a 15mm x 15mm x 20mm piece
Add 1 cup of water to a small pot, add the grated soap and bring to the boil.
Simmer until the soap has melted and take off the heat.
Stir in the washing soda and mix to dissolve.
Put back on the heat (at a gentle simmer) and stir for a few minutes to completely heat the washing soda and let it thicken a little.
Tip into the container you use for your stick blender. A bucket also works well.
Leave to cool. The soap will float to the surface of the water and set hard-ish. This may take overnight.
Once cool, use your stick blender to whizz the mixture up (carefully – you may need to cover the top). You can also use a blender or food processor. I don't find this works as well to blend the soap but your equipment may work differently.
Funnel into a suitable container. A plastic squeeze bottle is ideal.
If you want to add essential oils then add a few drops at this point and shake to combine.
The mixture will thicken over the next day but can be used straight away.
When adding the washing soda to the hot liquid it's good practice to do this in a ventilated area and use a dust mask or just a tea towel over your nose and mouth so you don't inhale fumes.
The water and other ingredients will separate in between uses - shake before using.
Not all castile soap is created equal. You might find yours makes a harder or thinner cleaner so you might need to adjust the ratios. Regular soap can also be used but check the ingredients first - the purpose of this cleaner is to avoid harmful ones!