Peel and finely dice the onion and garlic. Heat 1 tbsp. butter in a pot, fry onion and garlic over low heat until translucent. Add rice and sauté briefly. Season with pepper. Add broth and wine bit by bit, stirring from time to time. Add the next portion of liquid only after the rice has absorbed the liquid. Cook for a total of 30-35 minutes
Wash and drain the spinach. Wash sage, shake dry. Pluck off the leaves and cut into fine strips. Grate cheese. Add the spinach to the risotto about 5 minutes before the end of the cooking time and cook until the spinach has completely collapsed. Add lemon zest, 2/3 of the cheese and 4 tbsp. butter in flakes, season to taste with salt, pepper and lemon juice
In the meantime, peel the shrimps, except for the tail fin, and remove the intestines. Wash the shrimps and pat them dry. Heat the oil in a pan. Fry the prawns for 3-4 minutes while turning them, season with salt and pepper. Arrange risotto and prawns in bowls, sprinkle with remaining cheese