In a food processor, process the parsley, onion, bay leaves, garlic, peppercorns, orange zest, thyme leaves, and chile into a paste.
Heat the extra-virgin olive oil, 3 turns of the pan, in a large skillet over medium-high heat. Lightly brown the mushrooms for about 8 to 10 minutes, and then add the paste to the pan and stir. Add the shrimp and cook until they are pink and firm. Deglaze the pan with sherry, add the butter, and toss to melt. Serve immediately.