Onions Recipe

Peel and slice

Trim root and stem ends from the onions. Cut each onion in half pole-to-pole, then place cut side down and slice into 1/8- to 1/4-inch (3–6 mm) half-moons for even cooking.

Measure and have butter, oil, salt, pepper, and optional sugar ready.

Heat pan

Place a large, heavy skillet (preferably cast-iron or stainless steel) over medium heat. Add olive oil and butter. Heat until butter is fully melted and begins to foam but not brown, about 1–2 minutes.

Add onions

Add the sliced onions in an even layer. Stir to coat them with the butter and oil. Spread them out so they make good contact with the pan.

Initial cook

Cook the onions over medium heat, stirring every 2–3 minutes to prevent sticking and ensure even cooking. After 8–10 minutes they will be translucent and starting to soften.

Lower heat for caramelization

Reduce heat to medium-low. Continue to cook, stirring every 4–5 minutes and scraping any brown bits from the pan. If the onions begin to stick or brown too quickly, lower the heat. Total cooking time from this point is 20–35 minutes depending on desired color and sweetness.

Optional sugar and seasoning

Around the halfway point (after ~10–15 minutes of caramelizing), sprinkle the sugar (if using), half the salt, and half the pepper. Continue to cook and stir as directed.

Deglaze

When the onions are deeply golden-brown and jammy (after 25–40 minutes total), add the 60 ml water or broth to the pan to deglaze. Use a wooden spoon to scrape up any browned bits from the bottom. Let the liquid evaporate while stirring; this takes 1–2 minutes.

Adjust seasoning

Stir in the remaining salt and pepper and the vinegar if using. Taste and adjust seasoning as needed.

Remove from heat. Use immediately, or cool completely and store in an airtight container in the refrigerator for up to 5 days.