Prepare the grill for griddle setup. With the grill in the off position and cool, replace the left-side grate with the griddle. Preheat the grill with the control knob in the high position for 10 to 15 minutes.
Remove and discard the small, tough side muscle that might be left on each scallop. Brush the scallops on both sides with oil and season evenly with the salt and pepper.
Wipe the mushrooms clean with a damp paper towel and then remove and discard the stems. Cut each mushroom in half, place in a bowl, drizzle with oil, and toss to coat. Set aside.
Add the parsley and tarragon to the bowl of a food processor. Pulse until finely chopped. Add the mayonnaise and oil and pulse to blend to your desired consistency. Set aside.
Brush the griddle with oil. Brush the cooking grate clean with a stainless steel bristle grill brush.
Grill the scallops and the mushrooms on the griddle over direct high heat, with the lid closed, until the scallops are nicely seared and just opaque in the center and the mushrooms are heated through, 4 to 6 minutes, turning once. At the same time, grill the lemon halves on the cooking grate, cut side down, until nicely marked, about 3 minutes.
Remove the scallops, mushrooms, and lemon halves from the grill. Squeeze the lemon juice over the scallops and mushrooms and garnish with tarragon and sea salt flakes. Serve warm with the herb mayo on the side.
Let's Gear Up
Let's Gear Up
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