How do I cook a recipe when I do not have the equipment it asks for?

Most recipe equipment lists are aspirational. A few items genuinely do something nothing else does; a great many are a particular size and shape of metal that you already own in another form. The trick is telling those two categories apart before you find out the hard way.

Safety

Step by step

1. Ask what the item does, not what it is called.A ramekin is a small ovenproof dish. A springform tin is a tin whose sides come away so you do not have to turn a fragile cake out. A mandoline makes very thin, very even slices. Once you have the function you can see whether you own something that performs it.
2. Substitute tins and dishes on volume, and adjust the timing.Any ovenproof dish of about the right capacity will work. Fill it to a similar depth to the original — depth drives cooking time far more than shape does. Shallower means faster and more browned; deeper means slower and wetter. Check well before the stated time if you have gone shallower.
3. Improvise the common tools confidently.Rolling pin: a wine bottle. Piping bag: a food bag with a corner cut off. Steamer: a metal colander or sieve over a pan of simmering water with a lid, or a heatproof plate on three balls of foil. Cooling rack: the grill pan rack. Pastry cutter: a glass. Sieve for straining stock: a clean tea towel in a colander. Mortar: the end of a rolling pin in a sturdy bowl.
4. Improvise a lid, a rack and a bain-marie.A lid can be a baking tray, a larger plate or a doubled sheet of foil crimped round the rim. A roasting rack can be a bed of thickly sliced onion and carrot, which also flavours the juices. An oven bain-marie is any deep tray with hot water in it.
5. Know the small list of things with no real substitute.A pressure cooker cannot be improvised. A thermometer cannot be replaced by judgement for anything where safety depends on the number. A food processor's blade work — pastry, nut butters, fine emulsions — is only approximated by hand and by a lot of time. A stand mixer's long whisking of meringue and enriched dough can be done by hand but genuinely is hard work.
6. Check heat resistance before anything goes near an oven.Look for an ovenproof mark on glass and ceramic. Assume unmarked glass is not. Plastic handles, silicone spatulas and non-stick coatings all have maximum temperatures — usually printed on the item or its packaging. A pan handle that is fine on the hob may not be fine at 220°C.
7. Accept a different result rather than forcing the method.Sometimes the honest answer is to change the recipe. No cake tin means make a traybake. No blender means a chunkier soup. No barbecue means a very hot griddle pan and a smoked ingredient for the flavour. That is a better outcome than an unsafe improvisation.

Tips

• Two identical tins are worth more than one of each size. Most swaps come down to having something the right volume, and most kitchens are short on that rather than short on gadgets.
• Line an improvised tin with baking paper whenever the shape is not what the recipe assumed. It compensates for corners, seams and unknown non-stick behaviour.
• Weighing water is the quickest way to compare two dishes: 1ml of water weighs 1g, so fill the recipe's stated size on paper and fill yours, and you will know immediately whether it fits.

Common mistakes

• Putting a non-ovenproof glass dish into a hot oven — Ordinary glass and even some tempered glass fails from thermal shock and can break violently, sending fragments through the food and the oven. Only use glassware marked as ovenproof.
• Sealing a jar or a container to cook in it — Steam has to escape. A sealed vessel heated in an oven, a microwave or a pan of water builds pressure and can burst.

Questions people ask