Editor's note: Updated 3.12.20
A humble onion has to be the most versatile and important vegetable in the kitchen. Think of all the dishes that start with an onion: the stocks, the stews, and the sauces... we could continue. This simple infographic from Pounds to Pocket provides instructions for how to cook onions nine different ways, from caramelising them or sweating them down, to roasting them – whatever it takes to extract all that flavour and sweetness.
We’d probably suggest a few adaptations to these instructions, like maybe sweating your onions in butter to kick the richness of your dish up a level, but it’s a nice starting point if you want to know how to get the best out of the mighty bulb.
Do you want to learn from the pros too? Watch Michelin-starred chefs cook onions in different ways.
Nine different ways to cook onions
Caramelised onions
To achieve lovely sweet and soft onions to go in a frittata or omelette try caramelising them by cooking them in oil, butter and brown sugar until they are sweet and golden. Find out how to caramelise onions in the oven. You can caramelise almost any onion, but red onions work best because of their rich colour and sweetness.
Sautéed onions
Sautéed onions are perfect for pasta, burgers or pizza. Simply cook sliced onion in oil over a high heat until tender and golden. Shallots work especially well for sautéing.
Roasted onions
Bake onions in the oven to achieve sweet and mellow flavours, the perfect for accompaniment to sausages and mash, steak or a roast dinner. Use a large onion, white and yellow onions are great for this as their flavour deepens with the slow and low cooking method.
Sweated onions
Sweated onions are ideal for rice pilaf and white sauces as they retain their translucence as a result of the cooking process where the onions are sweated in a pot over the stove with their lid on. White onions will keep their subtle flavour when sweating.
Boiled onions
Simply boil whole onions in a pan of boiling water to tenderise them ready for adding to dishes like boeuf bourguignon. Use any onions for boiling, small pearl onions are especially good for boiling.
Grilled onions
Charring onions on the grill gives them a whole new dimension of smoky sweetness. Perfect for pairing with grilled meats, burgers or hot dogs. It depends on the meat you are serving them, but any onion works well for grilling, especially red onion.
Roasted whole onions
Roast onions in their skin until they are sweet and spreadable. Large white and yellow onions work very well as the skin imparts a delicious rich flavour to the delicate flesh. The perfect accompaniment to tacos, enchiladas or sandwiches.
Pickled onions
Finally, pickle onions in vinegar to enjoy their zesty tanginess all year round. Here's how to pickle onions. Smaller onions work best for pickling, as you can drop them in the brine whole. At their best paired with traditional meals such as fish & chips, ploughman’s lunches and pies.
Rather than just adding onions to your ingredients list, why not make them the star of the show with these delicious recipes: a rich and sweet caramelised onion tart that is soft and gooey, classic French onion soup with grated cheese croutons on top, or pickled red onions to go inside burgers, burritos and sandwiches or as a tasty accompaniment to Asian dishes.
They’re not just tasty and extremely versatile, as we’ve seen, but onions can provide plenty of health benefits, such as being rich in antioxidants, which may protect against certain cancers. Studies have also suggested that eating onions may help reduce your risk of heart disease, lower your blood pressure, help manage your cholesterol and reduce inflammation. Can you afford to miss out on all this?
For more information about onions, as well as which varieties to use for which different cooking method, this infographic of 21 different types of onion comes in very handy. If you’re keen to make some delicious pickled onions, look no further than pearl onions, red onions are great for roasting, and the more unusual maui onions are delicious turned into onion rings or caramelised.