Country: The Netherlands.
According to an AI identification system this might be a Fistulina hepatica.
Looking into it, Fistulina hepatica has an asexual state that does resemble what I see here (Article: Confistulina: a rare and little-known state of Fistulina hepatica)
But I am still not sure. Fistulina hepatica prefers to grow in oak and chestnut. Unfortunately I did not pay close attention at whether the tree was an oak tree when I took the picture, and from the small piece of bark visible in the photo it is hard for me to tell.
Here is a close-up of the surface of this fungus:
Looks like a beefsteak fungus that has grown abnormally due to its location on a saw off branch scar.
Thanks! So far I agree, I think it is a beefsteak fungus. It seems to be an asexual “anamorphic” state. Is there a reason why you think that being located at the saw off branch scar would induce abnormal growth? I am curious about what the trigger might be.