Ketchup

Ketchup is not just tomato paste with sugar. It's balance, built on purpose. Tomatoes give you acid and that deep savoury note food scientists call umami. Sugar tames the acid. Vinegar sharpens it back up. Salt joins the pot too, doing its own quiet work. Taste a spoonful on its own before you use it — sour, sweet, salty should all be there, none of them shouting over the rest.

Choose it by look and feel first. Tip the bottle and watch how it falls. Colour varies with the tomatoes and the cook, so don't judge by shade alone. Smell it. It should smell like cooked tomato with a clean vinegar edge, not like ketchup-flavoured syrup.

Some people say ketchup is just for hiding bad food and masking its flavour. No. Used properly, it sits alongside the taste of the dish; it doesn't bury it. That misconception leads to a real mistake: people drown a dish in ketchup to fix bland cooking, and end up with something that tastes only of sugar and vinegar. Season your food properly first. Then ketchup becomes a finishing touch, not a rescue mission.