Potato and Leek Gratin
Rinse and peel the potatoes and cut into 0.5 cm (approximately 1/8 inch) slices. Blanch in boiling salted water for 5 minutes, then drain.
Rinse the leeks and cut into 1 cm (approximately 1/2 inch) thick slices. Blanch the tomatoes, peel and cut into 1 cm (approximately 1/2 inch) thick slices. Cut the smoked pork into small cubes.
Brush a small baking dish with oil and arrange the vegetables in alternating layers. Season with salt and pepper and sprinkle with cheese between layers. Mix the sour cream with the egg, spread over the vegetables and sprinkle with cheese.
Bake in a preheated oven at 200°C (approximately 400°F) for about 30-40 minutes. If the surface is browning too quickly, cover with aluminum foil. Remove from the oven and garnish with basil just before serving.