Spring onion confit: tender bulbs and silky green tops slow-roasted in olive oil until jammy, caramelized, and meltingly soft — just five minutes of prep, then the oven does the rest.
I’m an equal-opportunity confit fan: I roast whatever the season brings in generous olive oil until it turns sweet, tender, and deeply flavored. Garlic, shallots, cherry tomatoes — same low-and-slow technique, different vegetable. Spring onions are especially lovely because they’re young onions harvested before they fully mature, so both the small sweet bulbs and the delicate green tops are entirely edible. They’re at their best in late spring and early summer, but you can find them year-round.
My love of cooked onions as a side started in Mexico City, where my family is from. In taquerías, cebollitas cambray arrive with the salsas, charred over open flame until sweet and blistered. This confit is the olive-oil-soaked, low-and-slow cousin of that — any color works, but purple spring onions turn especially pretty. The bulbs become jammy and caramelized while the greens soften and almost melt into the oil. That infused oil is part of the prize: keep it and use it in dressings, to finish pasta, to toss with roasted vegetables, or simply to dip crusty bread.
For extra caramelization on top, place the pan on the lowest oven rack during the last few minutes. You can also finish under a hot broiler for 30–60 seconds — keep the onions sitting in their oil, use a metal pan or cast iron, and position the pan about 6–8 inches from the element. Check every 30 seconds; it can go from perfect to burnt quickly.
Spoon the confit over eggs, toast, pasta, roasted vegetables, grain bowls, or sandwiches. Use the oil in vinaigrettes, to sauté greens, or to dress roasted potatoes. If you can turn on an oven and pour olive oil, you can make this. More alliums, always.
Spring Onion Confit
Ingredients
- 2 bunches purple spring onions, roots trimmed
- 1–1.5 cups extra-virgin olive oil, enough to mostly submerge the onions
- Kosher salt, to taste
Instructions
- Preheat the oven to 300°F (150°C).
- Arrange the spring onions in a single layer in an ovenproof dish. Trim roots so they sit flat if needed.
- Pour the olive oil over the onions so they are mostly submerged and sprinkle with kosher salt.
- Cover the dish with foil and roast until the bulbs are tender and jammy and the green tops are silky, about 50–60 minutes. For a touch of char, move the pan to the lowest oven rack for the last few minutes or briefly finish under the broiler (see notes).
- Let the confit cool completely. Transfer the onions and the oil to an airtight container and store in the refrigerator, keeping the onions fully submerged in oil. Use within two weeks.
Notes
To deepen caramelization, place the pan on the lowest oven rack for the final minutes of roasting. If you prefer a quick broiler finish, move the pan 6–8 inches below the element, keep the onions in their oil, use a metal pan or cast iron, and check every 30–60 seconds — it can burn fast. The leftover oil is flavorful and can be used in dressings, to finish dishes, or for dipping bread. If you use mild-green spring onions rather than purple, roasting time will be similar; smaller or thicker stalks may require slight adjustments.
Storage: Once cooled, keep the confit refrigerated in a sealed container with the onions submerged in oil for up to two weeks. Use the oil within that time for best flavor.
More Confit Recipes
Same low-and-slow technique, different vegetables. Try these other easy confit ideas:
- Garlic Confit — meltingly tender, caramelized cloves with fragrant infused garlic oil.
- Shallot Confit — jammy, sweet shallots that melt into dishes with rich shallot-flavored oil.
- Cherry Tomato Confit — slow-roasted cherry tomatoes that become sweet, jammy, and full of umami.
If you try this recipe, I’d love to hear about it. Leave a comment below or tag me on Instagram at @danielagerson so I can see your creations. Let’s make waves in the kitchen.