2. Lift burnt-on carbon from the hob and pans with a soda paste
Carbon is not grease. It is food that has gone past cooking into charring, and it bonds mechanically rather than dissolving, so surfactants alone do nothing. You need soaking plus gentle abrasion.
Mix baking soda with just enough water to make a paste the consistency of toothpaste. Spread a thick layer over the burnt rings on the hob, over the base of the scorched pan, or over the burner grates. Cover the paste with a damp cloth or a sheet of damp kitchen paper so it does not dry out, and leave it for an hour. Drying out is the single most common reason people report that it did not work.
Come back and push the paste with a plastic scraper or the edge of a wooden spoon. Most of the carbon will come away in sheets. What remains gets a second pass with the paste plus a nylon scourer, or for stainless pans, a sprinkle of coarse salt used as grit under a damp cloth.
The exceptions matter. Never use soda paste or salt on a non-stick pan — you will score the coating and it will then stick permanently. For non-stick, simmer water with a spoon of dish soap in the pan for five minutes and wipe with a soft sponge. And on glass or ceramic hobs, keep to plastic scrapers or a proper hob blade held almost flat; a scourer leaves a haze of fine scratches that shows up under kitchen downlights forever.