Equipment
Ingredients
Produce
- 600 g red onions, peeled
- 3 g fresh thyme, leaves picked
Pantry
- 30 ml olive oil
- 60 g dark brown sugar, packed
- 60 ml balsamic vinegar
- 3 g fine sea salt
- 1 g black pepper, freshly cracked
Nutrition (per serving)
Method
Halve the peeled red onions and slice them uniformly, about 3 to 4 millimeters thick.
Heat the olive oil in the heavy-bottomed pan over medium-low heat. Add the sliced onions and sea salt, stirring well with a wooden spoon to coat the onions evenly in the oil.
Reduce the heat to low. Cook the onions gently for 30 minutes, stirring occasionally to prevent sticking. The goal is to slowly draw out their natural sugars without crisping or burning them.
Stir in the dark brown sugar, balsamic vinegar, fresh thyme leaves, and black pepper. Increase the heat slightly to medium-low to bring the mixture to a gentle simmer. Cook for another 15 minutes, stirring frequently.
Remove the pan from the heat. Allow the marmalade to cool in the pan for 30 minutes before transferring it to a clean glass jar.
Chef's Notes
- Patience is the primary ingredient here. Rushing the initial 30-minute caramelization phase will result in a harsh, pungent flavor rather than the mellow, sweet profile required for a proper marmalade.
- The quality of your balsamic vinegar drastically affects the end result. A slightly older, thicker balsamic yields a richer, glossier glaze without introducing too much sharp acidity.
- For an elevated holiday variation, replace 20ml of the balsamic vinegar with a splash of ruby port wine or crème de cassis, adding it at the exact same stage.
Storage
Refrigerator: 1 month — Keep in a sterilized, airtight jar. Always use a clean spoon to serve.
Freezer: 3 months — Freeze in small airtight containers; thaw overnight in the refrigerator before using.
Reheating: Serve cold or at room temperature. Can be gently warmed in a saucepan over low heat if desired.
