4. Clean the oven overnight with soda, not fumes
Caustic oven sprays work fast and smell like a swimming pool accident. Baking soda works slowly and needs no ventilation plan, so it suits a flat, a rental or a house with kids and pets. Plan it for an evening when you are not cooking again.
Take everything out — shelves, side racks, the bottom tray. Mix about half a cup of baking soda with three or four tablespoons of water into a spreadable paste, and add a teaspoon of dish soap to help it wet the surface. Wearing gloves, coat every interior surface except the heating elements, the fan cover and the door seal. Getting paste on the element makes it smoke the next time you cook, so leave a clear margin.
The shelves go in the bath or a deep sink. Lay an old towel down first to protect the enamel, cover the shelves with hot water and a scoop of soda, and leave them alongside the oven.
In the morning, scrape the paste off with a plastic spatula into a bin, then wipe with a damp cloth, rinsing often. Stubborn corners get a spray bottle of vinegar: spritz the remaining soda film, let it fizz for a minute and wipe. That is the one place where combining the two is genuinely useful — you are neutralising leftover residue, not cleaning with the reaction.
The oven door glass usually has a removable inner panel held by two clips at the base. If yours does, take it out and clean the sandwich layer where the drips actually live.