A large cup fungus, with irregularly shaped fruitbodies that are usually found clustered together.  Initially, young cps have an olive tint inside; later the colour is red-brown or purplish-brown.   Identification is difficult, and microscopic examination of spores is needed for certainty

Peziza, and related species

microscope

We recommend that this is verified by an expert from a specimen before submission to NatureSpot.  Microscopic examination of spores is likely to be needed.  Also photograph in habitat, and note substrate

On soil in woodland and plantation, mostly coniferous.

https://www.first-nature.com/fungi/peziza-badia.php