Step 1

Clean mushrooms and remove stems.

Step 2

Simmer mushroom caps in salted water 5 minutes or until mushrooms are tender.

Step 3

Drain and transfer to a bowl. Add red onion, oil, vinegar, oregano, parsley, garlic, peppercorns, coriander and salt. Stir to combine.

Step 4

Taste and adjust seasoning, if needed.

Step 5

Marinate in the refrigerator for several hours or overnight. Bring to room temperature before serving.