Boil the diced potatoes in salted water until soft. Drain and mash with the egg, sour cream, and a pinch of salt. Set aside.
In a large skillet, heat olive oil over medium heat. Sauté chopped onion until translucent, then add garlic and cook until fragrant.
Add the minced meat and cook until browned.
Stir in bell pepper, peas, and tomato. Season with salt, black pepper, and chili pepper. Cook for a few minutes until vegetables soften.
Spread the mashed potatoes over the meat mixture or serve them side by side. Garnish with fresh herbs if desired.