The first properly cold morning changes what you want to eat. The tomatoes on the windowsill look sulky, and soup starts to feel like the right answer. Autumn is generous in Britain if you cook with what the fields are actually giving you — and it is the cheapest stretch of the year to fill the freezer.

What is genuinely at its best right now

British apples and pears arrive in waves from late August through to November, and the later varieties keep far better than anything shipped halfway round the world. Blackberries are free along most hedgerows if you get there before the birds, though pick above dog height and away from busy roads. Brassicas get sweeter after the first frost, which is why kale and sprouts taste so much better in November than they do in September.

• Fruit: apples, pears, quince, damsons, blackberries, late raspberries
• Roots: carrots, parsnips, beetroot, swede, celeriac, turnips, Jerusalem artichokes
• Greens: kale, cavolo nero, cabbage, leeks, chard, winter salad leaves
• Squash: butternut, crown prince, onion squash, pumpkins
• Others: mushrooms, chestnuts, cobnuts, Brussels sprouts from late October

Mushrooms are the great autumn pleasure and the great autumn risk. If you cannot identify one with total certainty, leave it in the ground and buy a punnet instead. The same caution applies to chestnuts: sweet chestnuts are worth the peeling, horse chestnuts are not food.

Eating seasonally without spending more

Seasonal food is not automatically cheap, but it usually is when you buy it the way the season dictates. A veg box shared with a neighbour often costs less per head than the same volume of supermarket produce, and it forces variety because you do not get to choose. Greengrocers and market stalls reward a regular visit; the last hour of a market is when traders fill bags generously to clear their tables. Ask what is going soft. A tray of bruised pears for a crumble is not a compromise, it is good shopping.

Buy loose where you can and cook whole where you can. Roast a whole squash, a tray of beetroot and a pile of onions on a Sunday, then eat from them all week. Root vegetables are the backbone of a cheap autumn kitchen: they keep for weeks in a cool, dark cupboard, they bulk out almost anything, and they cost very little.

Meal prep for shorter, darker evenings

Nobody wants to stand at the hob at half past six in November. The trick is to cook building blocks rather than finished meals, so a weeknight dinner becomes assembling rather than starting from scratch. One hour on a Sunday covers most of it.

1. Roast a tray of squash, carrots, parsnips, red onion and whole garlic cloves with a few sprigs of thyme. Forty minutes, one tray, no attention needed.
2. Simmer a pot of green lentils or a pan of beans while the oven is on. They keep for four days in the fridge and freeze well in flat bags.
3. Make a base sauce: onion, carrot, celery, tinned tomatoes, a splash of stock. Freeze it in two-portion bags.
4. Stew fruit — apples and blackberries with a little sugar and a strip of lemon peel — then cool and freeze in tubs.

Later in the week, dinner is a block plus something fresh. Wilt a bag of kale into the sauce, stir lentils through the roasted roots, spoon stewed fruit over porridge or yoghurt. Nothing takes more than fifteen minutes.

Four warming things to cook on repeat

Root vegetable and lentil stew

Soften an onion, a carrot and a stick of celery in oil. Add ground cumin and a little smoked paprika, then diced swede, parsnip and carrot. Pour in stock and a mug of green lentils, and simmer for half an hour until everything is tender. Finish with lemon juice and chopped parsley. It freezes well and improves overnight.

Squash, sage and butter beans

Roast chunks of squash with sage leaves and garlic until the edges catch. Mash a little of the squash into the pan with a splash of stock, add a tin of butter beans and warm through. A spoonful of yoghurt or a scatter of toasted seeds on top turns it into a proper supper.

Whatever-is-left soup

One onion, about 500g of any vegetable, a litre of stock and something to give it body — a potato, a handful of red lentils, a splash of milk. Simmer until soft, then blend or leave chunky. This is the recipe that empties the fridge drawer before the next shop.

Apple and blackberry crumble

Rub together plain flour, cold butter, porridge oats and a little sugar until it looks like rough breadcrumbs. Pile stewed fruit into a dish, cover, and bake at around 200°C (180°C fan, gas mark 6) for 35 to 40 minutes. Taste the fruit before you sweeten it; a good apple needs far less sugar than you think.

A few nutrition notes as the light drops

Autumn eating is mostly about fibre, warmth and enough of what sunlight usually supplies. UK guidance generally recommends a daily vitamin D supplement through the autumn and winter months, so it is worth asking a pharmacist what suits you, particularly if you are pregnant, breastfeeding or managing a health condition.

Lentils, beans and dark greens are good sources of iron, and the body absorbs plant iron better alongside vitamin C — a squeeze of lemon, some kale, a few berries. Fibre from roots, oats and pulses keeps you steady through the afternoon. Warm breakfasts such as porridge with stewed fruit do more for a cold morning than a slice of toast eaten standing up. And keep drinking water; tea counts towards fluids, but it is easy to run low when you are not thirsty.

If you have a medical condition, take regular medication, or are thinking about a significant change to how you eat, speak to your GP or a registered dietitian rather than working from a magazine page.

Start with one pot this week

Choose a single thing: a stew on Sunday, a box of apples turned into crumble filling, a tray of roots roasted while you get on with something else. Repeat it next week. By December you will have a freezer that can feed you on the evenings when cooking feels like too much, a lower food bill, and a kitchen that smells unmistakably like autumn.

Photo: Maciek Dostatni / Pexels