In a large bowl, add ground beef, 2 eggs, salt, black pepper, paprika, tomato paste, mustard, and chopped parsley. Mix gently with your hands until combined.

In a frying pan, heat a little vegetable oil and melt 30 g butter. Add chopped onion, bell pepper, and carrot. Sauté until softened.

Transfer the sautéed vegetables into the beef mixture. Add flour and mix well until everything holds together.

Boil 2 eggs for 7–10 minutes, peel, and grate them.

In a separate bowl, combine grated boiled eggs, grated semi-hard cheese, grated garlic, mayonnaise, salt, and pepper. Mix into a creamy filling.

Place the meat mixture on parchment paper and shape it into a rectangle about ½ inch thick.

Spread the egg-and-cheese mixture evenly over the meat. Lay thin slices of pickled cucumber in the center.

Using the parchment paper, carefully roll the meat into a log shape, sealing the filling inside.

Place the roll into a greased baking dish. Bake at 180°C (360°F) for 20 minutes.

Meanwhile, prepare the mashed potatoes. Boil 3 peeled potatoes with 1 teaspoon of salt until tender.

In a frying pan, melt 30 g butter and sauté mushrooms until golden brown.

Mash the potatoes, then stir in sautéed mushrooms and grated Parmesan for extra flavor.

For the sauce, mix tomato paste, soy sauce, and mustard. Pour over the baked meat roll, sprinkle with soft cheese, and bake for another 10 minutes until bubbly and golden.

Slice the meat roll and serve with mushroom mashed potatoes. Garnish with green onions.