1

Toss the shrimp, oregano, thyme, and garlic powder together in a medium bowl. Cover and refrigerate at least 1 hour or overnight.

2

Cut the head of Romaine in half lengthwise, leaving the root end in tact, so that the leaves on each half are held together by the root. Cut the radicchio in quarters, lengthwise, leaving the root end in tact, so that the leaves on each quarter are held together by the root.

3

Spray the grill rack or a large grill pan with nonstick spray; heat the grill or set the pan over medium heat. (Note: Never spray nonstick spray directly into a heat source, whether a grill or a stove.)

4

Lay the shrimp on the grill or in the pan. Cook until pink and firm, about 3 minutes, turning once. Transfer to a serving bowl.

5

Spray a wad of paper towels with a nonstick spray and wipe the grill rack or grill pan quickly – being careful not to burn yourself. Add the lettuces cut side down; cook until slightly wilted and marked from the grill, about 30 seconds, pressing down with the back of a large metal spatula or a small saucepan lid. Transfer the Romaine to a cutting board. Flip the radicchio quarters to the other cut sides; grill 20 more seconds. Transfer to the cutting board.

6

Roughly chop the Romaine and radicchio; add it to the bowl with the shrimp. Toss with the vinegar, salt, and pepper. Serve at once. Yields about 1 1/2 cups per serving.