Grilled California Bartlett Pear and Radicchio Salad with Candied Red Onions and Champagne Vinaigrette

Prepare the onions one hour in advance
To prepare the candied red onions, slice the onions into rings and place in a medium-sized bowl. Bring the sugar, vinegar and water to a boil and then pour it directly over the sliced onions. Immediately cover the bowl tightly with plastic wrap and set aside. Leave covered for one hour. Once candied, the onions can be kept in the refrigerator for up to one week.
Prepare the California pears and radicchio one hour in advance
Preheat the barbecue or indoor grill to medium. Cut the radicchio into quarters and then toss lightly in olive oil, salt and pepper. Slice each pear lengthwise into six slices (cut through the core). Grill the pears and radicchio just until tender, about two minutes per side. Remove the pears and radicchio from the grill and season the pears lightly with salt. Keep the pears and radicchio separate.
Both the pears and radicchio can be prepared in advance and left at room temperature for up to an hour, or refrigerated overnight.
Dressing
Whisk together the olive oil, champagne vinegar, thyme and honey and season with salt and pepper to taste.
Assembly and Presentation
Remove the core from the radicchio. Chop radicchio into strips. Place the strips of radicchio into the salad bowl. Peel the leaves off the endive and add them to the radicchio in the salad bowl. Cut the cooked pear slices in half. Be sure to cut around the core. Toss the pears together with the radicchio, endive, half the candied onions and the vinaigrette. Divide the salad evenly into four portions and garnish with remaining onions and shaved Asiago cheese.