Tinned Tomatoes

Tinned tomatoes are ripe plum tomatoes, peeled and packed in their own juice, either whole or chopped. In Indian cooking they go into the masala after the onions have browned, cooking down with ginger, garlic and ground spices until the oil separates. That is the start of butter chicken, chana masala, rajma and most North Indian gravies, and in the South a spoonful goes into rasam and tomato rice. Tomato paste is the same fruit reduced until thick, useful for colour and depth in small amounts, and sold in large catering tins for restaurants and big family cooking.

Whole plum tomatoes are the better choice for a slow gravy: crush them by hand into the pan and they collapse into a smooth sauce. Chopped tomatoes are quicker for a weeknight sabzi, pasta or shakshuka. Italian tomatoes tend to be sweeter and less acidic, so taste before adding sugar or extra tamarind. Small tins suit a single curry, and the catering sizes suit anyone cooking for a function or freezing sauce in batches.

Once opened, decant leftovers into a covered tub and use within three days, or freeze in portions for the next curry. You will find more cooked vegetables under tinned vegetables, including saag and spinach and sweetcorn and peas, and a tin of tomatoes goes naturally with ginger garlic paste and a good garam masala.