How do I cook vegetables properly?

Vegetables fail in two directions: undercooked and squeaky, or overcooked and grey. The right method depends mostly on water content and density — a carrot and a courgette want opposite treatment, and cooking them the same way guarantees one of them is wrong.

What you'll need

• Pan or roasting tin
• Salt
• Olive oil (optional)
• Steamer or colander (optional)

Step by step

1. Sort vegetables by density before deciding anything.Root vegetables, squash and brassica stems are dense and slow. Leafy greens, courgettes, peas and beans are fast and water-rich.
2. Roast dense vegetables at 200°C with oil and salt.Twenty-five to forty minutes. High heat concentrates sugars and browns the edges. This is where carrots, parsnips, squash and broccoli are at their best.
3. Boil green vegetables briefly in heavily salted water.Salt the water like pasta water. Two to four minutes for beans, peas and greens. They should be bright and still have bite.
4. Steam anything delicate or easily waterlogged.Broccoli, asparagus, courgette. Steaming keeps flavour in that boiling would wash out.
5. Sauté when you want browning and a fast result.Hot pan, not crowded, minimal stirring. Mushrooms, peppers and courgettes are much better browned than steamed.
6. Cut everything to a consistent size.Uneven pieces mean some are collapsing while others are still hard. This matters more than any other prep detail.
7. Season at the right moment.Salt roasted vegetables before cooking, boiled ones in the water, and sautéed ones near the end so they brown rather than sweat.
8. Finish with acid or fat.Lemon, vinegar, butter or good oil at the end transforms plain vegetables. This is the step that makes them worth eating.

Tips

• If green vegetables need to wait, plunge them into cold water to stop the cooking, then reheat briefly in butter. They stay bright green.
• Do not boil vegetables with a lid on if you want them to stay green — trapped acids dull the colour.
• Frozen peas, beans and spinach are frozen at peak freshness and are often better than tired fresh equivalents.

Common mistakes

• Boiling everything by default — It washes out flavour and turns dense vegetables to mush before the middles are done. Roasting suits most of them far better.
• Under-salting the water — Vegetables absorb seasoning while cooking. Salting only at the table never tastes the same.
• Cooking mixed vegetables for the same length of time — Carrots and courgettes need very different times. Stagger them into the pan rather than starting together.

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