How do I clean an oven?

Oven dirt is two different problems wearing the same colour. Fresh grease wipes off with any degreaser. Carbonised deposit — the hard black layer — has been chemically changed by heat and only comes off through prolonged contact with something alkaline, or through mechanical scraping. Almost every complaint about oven cleaning being hard work comes from trying to attack the second with a technique meant for the first.

Safety

What you'll need

• Bicarbonate of soda
• White vinegar in a spray bottle
• Rubber gloves
• Plastic scraper or old bank card
• Cloths and a bin bag
• Caustic oven cleaner for heavy deposits (optional)

Step by step

1. Take out the racks, side runners and anything else removable.They clean far better outside the oven and give you room to work.
2. Scrape out loose burnt debris from the floor of the oven.A plastic scraper won't scratch the enamel. Never use a metal blade.
3. Mix bicarbonate of soda with water to a spreadable paste and coat every internal surface except the elements and the fan.About half a cup of bicarb to three tablespoons of water. Keep it off the element — it will bake on and smell.
4. Leave it for at least 8 hours, ideally overnight.Contact time is the whole method. Two hours will disappoint you.
5. Meanwhile, soak the racks in the bath or a large tub with hot water and biological washing powder.Line the bath with an old towel first to protect the enamel. Biological powder digests the fat — leave them overnight too.
6. Wipe the paste out with a damp cloth, then spray any remaining residue with white vinegar.It foams as it reacts with the bicarb, which lifts the last film.
7. Clean the door glass last, scraping carefully with a plastic blade.Many doors unclip so you can reach between the panes — check your model before forcing anything.
8. Wipe everything down with clean water and dry it before use.Any bicarb left behind will smell on the next bake.

Tips

• Prevention beats cleaning: a sheet of foil or a reusable oven liner on the *floor* of the oven (never on the base plate of a fan oven with a lower element, and never covering vents) catches most spills.
• Wiping the oven while it's still warm after cooking — not hot — takes thirty seconds and prevents almost all baked-on build-up.
• If your oven has a pyrolytic cycle, use it. It burns deposits to ash which you then sweep out. Racks usually can't go through it — check the manual.
• A steam function or a tray of water heated at 100°C for 20 minutes softens light grease enough to make a quick wipe effective.

Common mistakes

• Spraying cleaner onto the heating element or fan — It bakes on, smells for weeks, and can damage the element.
• Using a metal scourer on enamel — It scratches the surface, and food then sticks to the scratches permanently.
• Not allowing enough soak time — Both bicarb and caustic cleaners work by prolonged contact. Rushing means scrubbing instead.
• Cleaning a self-cleaning (catalytic) liner with chemicals — Catalytic liners are designed to oxidise grease themselves and cleaners ruin the coating.

Questions people ask