Vegetable Cooking Guide

For best results and to minimise nutrient loss when cooking vegetables follow these basic rules:

Peel the skin thinly or leave it on. Nutrients are often at their highest concentration just beneath the skin. Peeling can mean the best part is thrown away.

Rinse vegetables. Use a sharp knife when cutting vegetables to minimise cell damage. Damaged cells release enzymes which destroy vitamin C.
Cook vegetables as soon as possible after preparation. Do not soak them. Vitamin C is destroyed when cut surfaces are exposed. Water soluble vitamins B and C will be lost in soaking water.
Use a small amount of water when cooking. The water soluble vitamins will leech into the cooking water which is often thrown away. Save vegetable water for use in soups, stocks and gravies.
Take care not to overcook vegetables. Most should be tender but still slightly crisp; this will vary with personal preference. Starchy vegetables, such as potatoes, should be tender throughout.
When stir-frying, cook at a high temperature for a short time and use as little oil as possible. Try using water in place of oil, or start with oil and sprinkle on water as the pan dries out.
The addition of baking soda to vegetables should be avoided. Whilst it does make the vegetables look greener, it destroys valuable vitamins.
Eat vegetables as soon as possible after cooking. Heat sensitive vitamins will be destroyed if held at a high temperature for prolonged periods.


Prepare vegetables, cut into evenly-sized pieces. If using whole vegetables, select those which are the same size. Place in boiling water 2–3cm deep. Cover tightly and bring back to the boil as quickly as possible, reduce heat and simmer gently. Cook until
tender when tested with a fork. Vigorous boiling will cause some vegetables, especially potatoes, to break up. Add extra boiling water if necessary. Drain and serve.
Approximate cooking times for boiling four servings of vegetables:
Cabbage, silver beet 4–6 minutes
Cauliflower, broccoli 8–10 minutes
Carrots (sliced), celery 12–16 minutes
Potatoes, parsnips, pumpkin, kumara 20–25 minutes


Prepare the vegetables, cut into evenly-sized pieces. Place in a steamer over rapidly boiling water. Don’t let the water touch the vegetables. Cover and adjust the heat to a steady simmer. Cook until tender. Add more boiling water if necessary.
Cooking times are approximately 5–10 minutes longer than boiling.


Microwave ovens cook food by using microwaves which penetrate the food and cause the moisture molecules to vibrate and heat up. The more water in the food the more quickly it cooks. Most vegetables are more than 90% water so they cook quickly.
Microwave ovens vary, so you will need to consult your manual for specific cooking times. Cooking times also depend on:
Size of vegetables.
Quantity being cooked.
Their density and moisture content.
The characteristics of your oven.
Any power fluctuations in your area.
Cut all pieces to a uniform size to ensure even cooking.
Use only a small quantity of water. Usually the water left clinging to the leaves after washing is sufficient.
Pierce whole or unpeeled vegetables before cooking to prevent bursting.
Cook vegetables on high power (100%).
Cook on automatic function, if possible, to take out guesswork.
Cover the dish with a plate, lid or plastic film to speed cooking and to keep the vegetables moist.
Arrange vegetables with the thickest stalks or spears, which need the most cooking, towards the outside of the dish.
Rotate or stir the vegetables during cooking to ensure an even result.
Micro waved vegetables continue cooking for an extra 2–4 minutes after the cooking period is finished. Make sure you allow for this to avoid overcooking.
Salt the vegetable after cooking, if at all! Salting before cooking causes vegetables to lose some of their moisture.


Stir-frying is a quick and easy cooking method. The vegetables are cooked rapidly in a minimum of liquid so fewer nutrients are lost or destroyed. You don’t need a wok, a large pan or saucepan works almost as well.
Have all the vegetables prepared before starting to cook.
Shred, dice or thinly slice the vegetables into pieces the same size.
Be sparing with oil. Start by heating the oil in the pan and if it dries out add a sprinkling of water. You will get the best results if the vegetables are hot and steamy.
Have the pan very hot before adding the vegetables.
Begin by cooking the denser vegetables (those that take longer to cook e.g. carrot and onion) and add the less dense ones towards the end of cooking time (e.g. cabbage or mushroom).
Cooking time is quite short for stir-frying so have the rest of the meal ready before you begin, that way you can serve immediately after cooking.


Baking is suitable for a wide range of vegetables. For dry baking, preheat the oven to 200C. Wash the vegetables; with many it is nicer to leave the skin on. Some vegetables need special attention, e.g. remove seeds from pumpkin. To ensure even cooking, make sure pieces, or whole vegetables, are the same size. Bake until softened when tested with a fork. As a guide, a medium-sized potato will take 45–55 minutes.
Vegetables also bake very well in a glaze, marinade or sauce. Many vegetables can be hollowed out and filled, e.g. marrow, capsicum, tomatoes and pumpkins.


Prepare the vegetables, e.g. zucchini cut in half lengthwise, halve tomatoes,  mushrooms, onion, or capsicum. Baste with oil, flavoured oil or marinade. Cook under, or over, direct heat, some will require turning. Cooking times vary depending on the intensity of the heat and the size of the pieces of vegetables. Pre- or partly cook
dense vegetables, e.g. carrot or potato, if you want to save cooking time, or just slice thinly.


Roasting is ideal for root vegetables. Preheat the oven to 200C. Wash and dry vegetables. Don’t bother peeling, except onions. Cut into similar sized pieces (e.g. potatoes, pumpkin, parsnips and onion) or leave small vegetables whole. Using different cuts, such as thin slices of pumpkin, not only shortens cooking time but adds variety and interest. Use only a small amount of oil. Place in a roasting dish or on a tray. Bake until tender. Cook the vegetables in a separate pan from meat and they won’t soak up the fat.
For crunchy roast vegetables, like wedges of potatoes, heat 2-3 tablespoons of oil in a roasting pan. Place 2–3 tablespoons of flour in a plastic bag, season, add the prepared vegetables and shake to evenly coat. Put the coated vegetables in the preheated oil, toss once or twice during cooking. Cooking times will vary depending on quantity cooked and size of pieces.
Slow-roasting is a popular cooking method that intensifies flavour. It is particularly good with tomatoes, asparagus and capsicum. Drizzle with olive oil, perhaps with a dash of balsamic vinegar, and sprinkle with black pepper. Bake in a slow oven, around 150C, until the vegetable is shrivelled, but not dried out. Slow-roasted vegetables are great as is, or tossed through leafy greens.