You can use a muffin mould for this.
pre-heat oven at 200°C.
put a small round bit of bread (buttered) on the bottom of each muffin hole.
Bake some mushrooms and onions in olive oil.
When ready, divide the mushrooms and onions over the mould.
Add whisked eggs to it. It's about an egg a quiche.
You can add grated cheese (I didn't)
Put in the oven for 20 minutes (but check before you take them out)