Peel and finely chop the onion. Heat the oil in a pot. Add the frozen spinach and about 100 ml of water, cover and let thaw for 10-12 minutes. Then steam open for 3-4 minutes. Wash mint, shake dry, chop and fold into the spinach.
Season to taste with salt, pepper and lemon juice.
Cut mozzarella into 4 slices. Coarsely chop the nuts and roast them in a pan without fat. Take out. Fry the ham in the pan until crispy on one side, then turn it over and place 1 slice of cheese on top of each and melt it slightly.
Arrange the spinach as a blob on four plates. Place 1 slice of ham with the cheese on each plate. Sprinkle with nuts and serve. Baguette tastes good with it.