This is our Project 365 blog: our year in photographs.
I get those in my compost heap and originally in my garden too. I found out what they were... Peziza Vesiculosa, the Blistered Cap fungus. Unfortunately not edible ("poisonous unless well cooked", my scribbled note says), but they only grow in rich soil. Amazing what you find on the A to Z Challenge, isn't it!
Thank you for the info. Good to know my soil is rich. Thankfully, we don't really like mushrooms, so we haven't tried to eat them :)