Onion Relish – a Homemade Condiment to Elevate your Food Parties
Onion relish is a condiment or sauce made from onions that have been cooked down. It’s not a must but it can be combined with various other ingredients to create a flavourful and versatile accompaniment that pairs well with a multitude of dishes. It will come as no surprise that it is the perfect condiment when organising a barbecue.

The onions are usually thinly sliced or chopped and then cooked until they become soft and translucent. Vinegar, often cider vinegar or white vinegar, is added to provide acidity and enhance the flavour. We choose to use red wine vinegar in this recipe since we use red onions. Sugar is added to balance the tanginess of the vinegar and bring a touch of sweetness to the relish. In this recipe we didn’t add extra spices but common spices and seasonings used may include black pepper, mustard seeds, chili flakes, garlic, and herbs like thyme or bay leaves.
How to best serve onion relish
Onion relish can be served as a topping or accompaniment for various dishes. It pairs perfectly with burgers, hot dogs, sandwiches, grilled meats, sausages, cheese, or elevates a salad to the next level! It adds a burst of flavour and texture, complementing the savoury elements of the dish.
Cutting the onions might bring tears to your eyes, but this recipe is straightforward and quick to prepare.
Also read about other condiments and spices.

Onion Relish
EQUIPMENT (click pictures for details)
Ingredients
- 4 pcs Red onions diced sliced or diced
- 30 gr unsalted butter
- 1 tsp Salt
- 2 tbsp light brown sugar 25 gr
- 350 ml water 250+100
- 50 ml red wine
- 4 tbsp red wine vinegar 40 ml
Instructions
- Sweat the sliced onions in the butter over a low heat, add the salt and cook until tender.Add the sugar, 250 ml water, red wine and the vinegar. Increase the heat and cook until the liquid evaporates.
- Taste the red onion doneness and add the rest of the water if necessary.
- When the onion relish is cooked it will be sticky like jam.
- Season to taste and transfer into sterilised jars, close the lid, and allow to cool.