1 tablespoon olive oil
250 grams mushrooms, button or cremini, halved if small, quartered if bigger
4 tablespoons white wine vinegar or sherry vinegar
1 tablespoon sugar
Heat the oil in a medium nonstick skillet over medium high heat until hot. Add the mushrooms, salt and black pepper to taste, stirring often, and cook for about 6 minutes or until golden and slightly brown. Remove the skillet from the heat, and transfer the mushrooms into a bowl. Add the vinegar and sugar, toss until well mixed. Serve or keep in an air-tight jar or container for up to at least 2 weeks.