Caramelized Onion, Mushroom & Bacon PierogiesClassic Cheddar

Cook the bacon over medium-high heat until tips begin to crisp.With bacon and drippings still in the pan, add the onions, mushrooms, thyme, balsamic vinegar, sugar and salt. Cook for 2-3 minutes until onions begin to brown. Reduce heat to medium-low and simmer, covered with lid for 10-15 minutes; stirring occasionally. Set aside.Heat a skillet with butter and sauté pierogies according to package directions.Top pierogies with caramelized onion mixture before serving.