Prepare rice in boiling salted water according to the instructions on the packet. Peel garlic and dice finely. Clean, wash and chop the celery. Wash nectarine and cut into slices from the stone.
Rinse the prawns and pat them dry. Heat the oil in a coated pan. Fry the prawns and garlic for approx. 3 minutes, turning them over and taking them out. Put celery in the pan, add 4 tablespoons of water and steam covered for about 5 minutes.
Add the shrimps and nectarines. Season with salt and pepper. Stir in sweet and sour sauce and ketchup. Drain the rice and serve with the shrimp pan. Garnish with a slice of lemon.