Salt, fat, acid and heat are the four fundamental elements of good cooking, says New York Times food columnist and former chef Samin Nosrat.
Nosrat has never cooked with recipes – she learnt to cook at San Francisco restaurant Chez Pannise where the menu changed every day – and believes they're too static.
She wanted to write a cookbook, but not "a traditional-looking book with photos of dishes and instructions about how to make them" – a book teaching people how to think for themselves in the kitchen.
The result is Salt, Fat, Acid, Heat.
These four points of the cooking compass can help you tweak things to make your cooking taste better (no need for a recipe) Nosrat says.
How does Nosrat sum up her food philosophy?
"Taste and taste and taste again and get it just right for you that day in the kitchen."
Salt's main role in cooking is to enhance flavour.
"It opens and unlocks aromatic compounds for us to experience and sense – and so much flavour is aroma."
When adding salt, the only way is to taste.
Fruit and vegetables are alive when they come off the tree or out of the ground and their level of sweetness can change in a matter of days.
"Today's tomorrow may not be tomorrow's tomato."
With fat, it might sound simple but be sure you're choosing the right fat for your best dish, Nosrat says.
In France, they usually cook with duck fat and butter, in Italy, olive oil, in India, ghee and in Korea, neutral vegetable oil.
"If I am trying to took Korean or Indian food and I start with olive oil, my food will never taste right because it will be flavoured with olive oil from the foundation."
Acid is a 'clinical sounding' thing to add to your food, but essential for creating contrast.
"In a lot of dishes you shouldn't be able to taste the acid. All it does is enliven things that may otherwise be falling flat."
if your dish is a little too rich, a little too starchy or even just a little monotone, acid could be the answer.
Once Nosrat was making a simple carrot soup with onions, butter, oil, water, carrots and salt.
She thought it was perfect, but another chef on his way up the stairs said 'That needs some vinegar. Add a capful of vinegar."
She thought he was crazy but did what he said.
While you couldn't taste the vinegar, it provided a contrast to the sweetness of the carrots, she says.
"Suddenly it wasn't just one note anymore, it was multiple notes."
Nosrat's fridge is full of acidic foods – "pickles, cheese, fermented dairy, sour cream, tangy yoghurt… all these things we will often add a spoonful of right at the end."
Heat is temperature heat, rather than spice heat, i.e. "what is happening in the pan".
Learning how to cook with heat allows you to get your food done on the outside and the inside at the same time just the way you like - an essential skill when you want to brown on the outside and leave the inside tender (for steak, say) or expertly turn something tough, like pulses, tender.
Because a lot of restaurant food is heavily seasoned or over-rich, so when she lefre restaurants Nosrat had to 'renovate her palate'.
Now she finds processed food exhausting palate-wise, too.
"At the first bite I'm 'These are so good, these chips are so good'. Then by the third or fourth bite it's almost like I have a hangover of too much salt, too much fat."