1. Place peeled and cubed potatoes in a large pot and cover with cold water. Add a pinch of salt and bring to a boil over medium-high heat. Cook until tender, about 15-20 minutes. Drain well and return to the pot.
2. Mash the potatoes with butter and a pinch of salt and pepper until smooth but still fluffy. Set aside to cool while you prepare the filling.
3. Heat olive oil in a skillet over medium heat. Add chopped onion and garlic, sautéing until fragrant and translucent, about 3-4 minutes.
4. Add ground beef (or turkey) to the skillet, breaking it up with a wooden spoon. Cook until browned and cooked through, about 6-8 minutes. Stir in the chopped bell pepper, smoked paprika, oregano, salt, and pepper. Cook for another 2 minutes to let the flavors meld. Remove from heat and let cool slightly.
5. Once the filling and mashed potatoes have cooled, mix in the beaten egg and shredded cheese into the potatoes. This helps bind the cakes and adds flavor.
6. Lightly flour your hands and a flat surface. Take about 1/4 cup of the mashed potato mixture and flatten it into a disc in your palm. Spoon about 2 tablespoons of the meat filling into the center.
7. Carefully fold the potato around the filling and shape into a compact cake, sealing the edges as best as you can. Repeat until all the mixture is used.
8. Heat about 1/4 inch of vegetable oil in a large skillet over medium heat. Once hot (a breadcrumb should sizzle immediately), fry the cakes in batches. Cook each side for 3-4 minutes or until golden brown and crispy.
9. Transfer cooked cakes to a paper towel-lined plate to drain excess oil.

A little kitchen secret: When I first started experimenting with stuffed potato cakes, I found that cooling the filling and mashed potatoes thoroughly made shaping much easier. Warm potatoes can be sticky and stubborn, but cooled ones behave much better. Also, don’t rush the frying step—medium heat ensures crispy outsides without burning.