Prepare the Vegetables: Grate the potatoes and carrot. Finely chop the leek or onion and set everything aside.
Mix the Ingredients: In a large mixing bowl, combine the grated potatoes, grated carrot, chopped leek or onion, eggs, kefir (or yogurt), and wheat flour. Stir everything well to form a thick batter.
Add Tomatoes: Dice the tomatoes and add them to the mixture, gently folding them in.
Prepare the Pan: Preheat the oven to 180°C (350°F). Grease a baking dish with oil and pour the mixture into the dish, spreading it evenly.
Top with Cheese: Grate your choice of cheese and sprinkle it generously over the top of the potato mixture.
Bake: Place the dish in the oven and bake for about 40-45 minutes, or until the top is golden brown and crispy, and the center is cooked through.
Serve: Once done, let it cool for a few minutes, then slice and serve. Enjoy!