Ingredients
1 pound small fresh mushrooms1 small onion, thinly sliced1/3 cup white wine vinegar1/3 cup canola oil1 teaspoon salt1 teaspoon ground mustard
Preparation
In a large saucepan, combine all ingredients. Bring to a boil over medium-high heat. Cook, uncovered, for 6 minutes, stirring once. Cool to room temperature. Transfer to a large bowl; cover and refrigerate overnight.
