Grilled Hearts of Romaine with Blue Cheese Vinaigrette and Pickled Onions

Preparation

1. For onions:

   Step 1

   Combine first 5 ingredients and 1/4 teaspoon coarse salt in medium saucepan. Bring to simmer over medium heat. Add onions and stir to blend; return to simmer and cook 2 minutes. Remove from heat; cool to room temperature, about 1 hour. Season with freshly ground black pepper and more salt, if desired. DO AHEAD: Can be made 1 day ahead. Cover; chill.

2. For salad:

   Step 2

   Prepare barbecue (medium- high heat). Combine vinegar and mustard in bowl. Gradually whisk in oil. Season with coarse salt and pepper. Mix in 1/2 cup cheese.

   Step 3

   Brush cut sides of romaine with olive oil, then sprinkle with coarse salt and pepper. Grill until cut sides are lightly charred, about 2 minutes per side.

   Step 4

   Divide grilled romaine among plates. Top with vinaigrette, pickled onions, and blue cheese.