Other fillings that may be used:
Filling 2:
1 tablespoon butter
1/2 cup minced onion
4 ounces mushrooms, finely chopped
1/2 cup sauerkraut, drained and chopped
1/4 teaspoon salt and pepper
Filling 3:
1 tablespoon butter
1/2 cup minced onion
1 cup mashed potatoes
1 cup cottage cheese, drained
Find it online: https://hilahcooking.com/pierogi/