Begin by boiling diced potatoes in a large pot of salted water for about 20–30 minutes, or until fork-tender. Drain and let cool, then mash and season with salt and pepper.

In a skillet, heat the oil over medium heat. Sauté onions for about 5 minutes until translucent, then add garlic and mushrooms. Cook for an additional 15 minutes, stir in lemon juice, dill, and season.

In a mixing bowl, combine cooled mashed potatoes with gluten-free flour, mix well. Shape potato mixture around a tablespoon of mushroom filling, forming round cakes.

Heat oil in a frying pan over high heat. Fry the cakes for about 2 minutes on each side until golden brown. Serve warm.