Red Onion Marmalade. Directions. Cook 2 thinly sliced large red onions in a skillet with 1/4 cup olive oil over low heat, covered, until golden, 30 minutes. Stir in 3 tablespoons cider vinegar, 2 tablespoons brown sugar and 1 teaspoon grated peeled ginger; season with salt.
Soft, sticky onion marmalade - great with pâtés and terrrines or a ploughman's lunch Halve and thinly slice the onions, then thinly slice the garlic. Melt the butter with the oil in a large, heavy-based saucepan over a high heat. Tip in the onions and garlic and give them a good stir so they are glossed with butter.
It's called a marmalade because the knife cut we use is long and stringy, kind of like a citrus. Thinly slice the onions by first cutting in half, then removing the core at an angle. Thinly slice the onions like a fan. Over medium heat, add the oil followed by the onions. The onions will start to sweat and cook down, releasing their liquid.
Step Five – The onion marmalade is ready once the onion is a rich dark brown, shiny and sticky with no liquid in the pan. You can test it by drawing a spoon across the bottom of the pan, where it will leave a clear trail for several seconds. Remove from the heat and transfer to clean sterilized jars and seal.