Help please!

Karcher manufacture lots of different cleaning devices.

Oh - I've got a Karcher but only use it to clean windows...

Yes, Norah did suggest a pressure washer (Karcher).

Did anyone suggest a pressure washer?

Great thanks! Pressure washer here I come!

As it's on stone slabs and not carpet or material can't you carefully slide it off with a palette knife

When the wax is stiff, chip or peel it away. There will probably be a grease spot. Use a brush and some washing up liquid, right from bottle, and scrub. Then dump hot water over, repeat until the stain is gone. I also use the karcher after the washing up liquid, that usually works well for food, berry stains and colour crayons.

DH used wax a lot for work and used an iron over brown paper on any spills. I think you can do it over greaseproof paper too.

Or put ice cubes in a plastic bag on the spill and then pick off when it is solid!