I've read countless "handy hints" and "tips" for cooking. One of them said that professional chefs have 4 great "rescue ingredients". Or, to put it another way - ways to cheat the tastebuds by adding instant flavour.
I'm not recommending you adopt them for every day use. But they may help you out of a tricky spot (or make you aware of what is hiding in the ostensibly simple dish you buy in a restaurant)
They tend to be ways of boosting a dish by adding to one of the 5 basic taste sensations- sweet, salty, bitter, sour, savoury or umami.
This is the list I'm aware of - let me know if you come across any others!
Sugar and salt I understand that salt opens the palate and helps us enjoy the flavour in dishes. When boiling vegetables (e.g. carrots) the combination of a teaspoonful of sugar and quarter teaspoon/pinch of salt added to cooking water can really lift the flavour, particularly if the vegetables are a little old.
Of course, you can educate your palate to enjoy less salt, or none at all, and use other things to give the flavour.
But the basic principle of sweet and salt together being "tasty" explains their presence in prepared foods. Urban legend has it that KFC use a combination of a little salt, sugar and chicken stock on their fries, to make them moreish.
Brown sugar can disguise the salty taste in an over-salted soup or stock. The salt is still there though - not good for health or blood pressure!
And of course salt is added to chips. I was told that this is partly to absorb excess fat, although I don't know if this has a scientific basis.
My summary : use sparingly - don't add salt or sugar as a general rule. Use it in moderate quantities where it has maximum impact, as part of a balanced diet. It can be great for bringing out flavour in vegetables, but you don't want to rely on the sugar/salt combination in everything you eat.
Butter, melted or whole, adds fat, but always tastes good. Hence it's role as a chef's rescuer! Be careful for the calories, and enjoy immensely in small quantities!
Worcester Sauce Adds flavour and richness - to pasta sauces or cheese on toast!
Ground white pepper This can give food a body and zest. Used in casseroles or seasoned vegies it can give a real lift. Similarly, a sponful of tomato paste can add body and richness, and excite the "umami" taste.
Cream for creamy-ness (and calories!)
Lemon or lime juice can cut through a rich dish
Parmesan cheese also provides the umami flavour.
And then there's MSG - the original umami. I don't use it or eat it myself, although some scientists claim that the MSG/chinese restaurant syndrome is due to things other than MSG, and it's not actually bad for you. It's widely added to food in many parts of Asia. Up to you!
I know that's more than 4 taste tricks - the original four were, I think, salt, brown sugar, worcester sauce and butter. If you know of any other tricks and tips, let me know!
Update: When I compiled this list, I forgot to add Sherry. It can be a miracle ingredient in soups. A couple of tablespoonfuls will make an ordinary soup (dare I say it - even a tinned soup - taste fabulous.