Sauté the onion in the warm butter until light yellow. Then add the prepared vegetables and stew briefly. Add the soup and cook for ten minutes with the lid closed.
Then add the spinach, milk and croissants. Make the soup for another ten to twelve minutes until the pasta is soft.
Add the cream and season the soup with salt and freshly ground pepper. Arrange in plates or soup cups and sprinkle thickly with cheese. Serve immediately.
Tip: Did you know that one bowl of spinach already covers the entire daily requirement of vitamin K and beta-carotene?