What to keep on the wooden table to make the surface heat resistant?
When we had a wooden table as a child for every day use, we kept a layer of tempered glass that sat up on silicone feet so there was a thin air gap between the table and the glass. The glass covered the entire surface of the table, so there was no risk of spills or hot items damaging the actual wood surface of the table.

I would look into something that definitely had an air gap below it. A stone, ceramic, or glass cutting board (or a tile tray) with feet would work.