Potato and Cheese Pierogi

Ingredients

• packed dill sprigs
• olive oil
• fine salt
• small celery roots , scrubbed and peeled
• fine salt, plus more
• russet potatoes , peeled and coarsely chopped
• smoked twaróg, or farmer cheese
• finely grated szafir, Džiugas, or parmesan cheese
• caraway seeds, plus more for serving
• Freshly ground black pepper
• Sour cream, for serving
• all-purpose flour, plus more for kneading
• cold-pressed canola or extra-virgin olive oil