Peel the shallots and cut into thin slices. Cut bacon into fine strips. Clean mushrooms, wash if necessary and cut into slices.
Bring 3/4 l water with broth to the boil. Remove the pot from the heat, add milk and stir in the puree flakes. Add frozen peas, bring everything to the boil once and leave it on the switched off stove.
Season to taste with salt, pepper and nutmeg.
In the meantime, fry the bacon in a pan without fat for about 5 minutes until crispy. Fry the mushrooms and shallots for about 3 minutes. Serve the soup with the bacon.