Directions

1. Place the cabbage, butter, and mushrooms into a large pot or Dutch oven with lid. Season with seasoned salt, and pour in the beer. Bring to a boil over high heat, then reduce heat to medium-low, cover, and simmer. While the cabbage is simmering, combine the kielbasa, garlic, onion, Worcestershire sauce, and balsamic vinegar in a skillet. Bring to a simmer over medium-high heat, and cook until the onions have turned translucent, about 5 minutes. Stir the sausage mixture into the cabbage mixture, recover, and continue simmering until the cabbage is tender, about 15 to 20 minutes more.
2. About 15 minutes before the cabbage is ready, fill a large pot with lightly salted water and bring to a rolling boil over high heat. Once the water is boiling, stir in the pierogies and return to a boil. Cook until the pierogies float to the top, 5 to 10 minutes; drain.
3. Heat the vegetable oil in a clean skillet over medium-high heat. Add the drained pierogies, and cook until golden brown on both sides, about 5 minutes. Gently stir the browned pierogies and diced tomatoes into the cabbage mixture, and cook 5 to 10 minutes to reheat.