The most common reason home cooking tastes flat is not lack of spice. It is lack of salt — added too late, too little, or both. Understanding salt is the single biggest improvement most cooks can make.
Salt brings out flavour
Salt does not just taste salty. It opens up the existing flavours in food, making everything else taste more like itself. Under-salted food tastes muted; properly salted food tastes alive.
Salt at every stage
Salt the onions as they soften. Salt the meat before it sears. Salt the pasta water. Salt the sauce. Each layer matters. Salting only at the end leaves the seasoning sitting on top.
Use coarse or flaky salt
Fine table salt is hard to control — small amounts taste salty fast. Flaky sea salt or coarse kosher salt is easier to season with by feel.
Taste, season, taste, season
The order is: cook a little, taste, season, cook a little more, taste, season. Never season once at the end and hope.
If something tastes flat, try salt first
Before you add another herb, more pepper, or a splash of vinegar, try a pinch more salt. Eight times out of ten, that is what was missing.
Salt is not the enemy. Salting your own food, fresh, well, at home, is healthier than eating restaurant or shop-bought food that does the salting for you. The difference between a passable dinner and a memorable one is often just a quarter teaspoon more.