Baked Onions – QUICK and Gratin

Baked onions with gratin are an irresistible side dish, both with white varieties and with the delicious red Tropea onions. Without blanching the onions, this easy and quick recipe will allow you to enjoy all the natural taste of onions. You can choose wedges or thin slices, and to make each bite a burst of flavor, you can add balsamic vinegar or caramelize them by sprinkling sugar before baking.

SEASON of #fresh onions: from March to December.
Onion harvesting period:

– Red of Tropea: from March to April (early ones) from June to July (late ones) from August to October (winter ones)

of Giarratana: from July to August

RECIPES with onions:

Quick and easy baked onions with gratin
  • Difficulty: Easy
  • Cost: Economical
  • Preparation time: 10 Minutes
  • Portions: 4People
  • Cooking methods: Oven
  • Cuisine: Healthy
  • Seasonality: Spring, Summer, and Fall
60.00 Kcal
calories per serving
Info Close
  • Energy 60.00 (Kcal)
  • Carbohydrates 11.68 (g) of which sugars 5.30 (g)
  • Proteins 1.38 (g)
  • Fat 1.29 (g) of which saturated 0.22 (g)of which unsaturated 0.04 (g)
  • Fibers 2.13 (g)
  • Sodium 101.90 (mg)

Indicative values for a portion of 60 g processed in an automated way starting from the nutritional information available on the CREA* and FoodData Central** databases. It is not food and / or nutritional advice.

* CREATES Food and Nutrition Research Center: https://www.crea.gov.it/alimenti-e-nutrizione https://www.alimentinutrizione.it ** U.S. Department of Agriculture, Agricultural Research Service. FoodData Central, 2019. https://fdc.nal.usda.gov

Baked Onions

  • 3 onions (about one pound)
  • 1 tbsp extra virgin olive oil (or peanut oil)
  • to taste salt

Quick baked onions with gratin

  • Wash and cut the onions into uniform wedges, slices, or rings, then place them in a bowl and season with oil, salt, and preferred herbs. Mix.

    Place the onions (white or red) on the baking tray, forming a single layer.

  • COOK for 15-20 minutes (the cooking time depends on the thickness of the onions), first 10 minutes in a fan oven at 320°F and then 5-10 minutes in a static oven at 356°F.

    baked onions gratin and sliced 130442
  • Wash and cut the onions into uniform slices, then place them in a bowl and season. Mix everything. Then place the onions, forming a single layer, on the baking tray.

    COOK for about 15 minutes in a static oven at 356°F.

    baked onions - white sliced

STORAGE of baked onions

Before storing them in an airtight container, let them cool completely. In the refrigerator, they will remain tasty for 3 days, while in the freezer they last for more than 3 months.

How to cut an onion without crying?

My favorite technique is under the kitchen hood, or try these other tips:

Cold water: before starting to cut the onion, soak it in cold water for a few minutes to reduce the spread of irritants into the air.

Freezing: place the onion in the freezer for about 15-20 minutes before cutting to slow the diffusion of irritants.

Ventilation: make sure there’s good ventilation in the area where you’re cutting the onion to disperse the irritants.

Quick cutting: try to cut the onion as quickly as possible to reduce the release of irritants.

Sharp blade: use a sharp knife to cut the onion cleanly and reduce the release of irritants.

Cutting under running water: you can cut the onion under running water to contain the irritants.

Mask or swimming goggles: wearing a face mask or swimming goggles can prevent irritants from reaching your eyes.

Chewing gum: some people find that chewing gum while cutting the onion can help prevent tears.

Refrigerated onion: store the onion in the refrigerator before cutting to reduce the release of irritants.

Specific cutting techniques: some cutting techniques, like radial or wedge cutting, can reduce the release of irritants.

  • What to pair with red onions?

    Some options to pair with red onions (from Tropea):
    Fresh salads – Add them to salads with lettuce, arugula, or spinach.
    Burgers and sandwiches – Thin slices of red onion add crunch and flavor to your burgers and sandwiches.
    Sauces and dressings – Prepare sauces like pico de gallo or tzatziki.
    Fish dishes – Like sushi or tuna salads, with slices of red onion.
    Pizza and focaccia – Use them as a topping for pizza or focaccia.
    Cheeses – Pair them with fresh or slightly aged cheeses, like mozzarella or goat cheese.
    Baked dishes – Add red onions to quiches, frittatas, or vegetable gratins.

  • When should you not eat onions?

    Avoid consuming onions when having gastrointestinal issues like stomach acidity or heartburn. Onions can increase gastric acid production, worsening symptoms. Additionally, if you are allergic to onions or the ingredients present in them, it’s best to avoid them to prevent adverse reactions.

  • Which onion is more digestible?

    Among onion varieties, Tropea onions are often considered more digestible compared to other varieties. Red onions are sweet and delicate, with a higher sugar content than other onions, making them easier to digest. This characteristic makes them a suitable choice even for those with gastric sensitivities. However, the digestibility of onions can vary from person to person, so it’s always advisable to listen to your body and observe how it reacts to different varieties of onion.

  • How to make onions less indigestible?

    To make onions more digestible and reduce the risk of indigestion, you can adopt some strategies. Opt for sweeter onion varieties like Tropea onions, which are naturally more delicate and less irritating to the digestive system.

    Before using onions in raw recipes, like in salads, soak them in boiling water for a few minutes and then cool them quickly (this will make their flavor less aggressive), or you can soak them in cold vinegar for at least 20 minutes.

    Cook the onions thoroughly, as cooking makes the onions softer and breaks down some of the substances that may cause irritation. Moreover, you can cook the onions slowly over low heat until they become soft and sweet, making them easier to digest.

    Cut the onions into very small pieces or slice them thinly to reduce the fiber content and ease digestion. Combine onions with herbs and spices known to promote digestion, such as ginger, fennel, or mint.

  • Which onion is the healthiest?

    Tropea onions are often considered among the most beneficial onion varieties for health. These onions are sweet and delicate, characterized by a high content of antioxidants, vitamins, and minerals such as vitamin C and potassium. Thanks to these properties, Tropea onions can contribute to supporting the immune system, cardiovascular health, and overall well-being.

  • What to eat after eating onions?

    After eating onions, it’s advisable to opt for light and bland foods to facilitate digestion. You can consider foods like white rice, boiled potatoes, natural yogurt, or fresh fruit. Avoid heavy or high-fat meals, as they may increase the risk of indigestion. Drinking water or herbal teas can also help facilitate digestion. Listen to your body and choose foods that make you feel comfortable after consuming onions.

  • How to remove the strong taste of onions?

    To mitigate the strong taste of onions, you can adopt several strategies. One of the most effective is soaking. Slice the onions thinly and soak them in cold water for about 15-30 minutes. This process helps to reduce the intensity of the flavor and pungent odor. You can also rinse the onions under running water before using them to remove some of the soluble compounds that contribute to the strong flavor. Additionally, slowly cooking the onions over low heat or caramelizing them can make their flavor sweeter and more delicate. Experiment with different preparation techniques to find what works best for you and the dish you’re making.

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Sara Grissino

Simple and seasonal Italian recipes, often vegan or vegetarian, with fresh and sustainable ingredients for healthy and delicious cooking.

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