In small bowl, whisk together butter, 3 tbsp (45 mL) of the oil, vinegar, thyme, mustard, honey and garlic. Remove 2 tbsp (25 mL) of the herb mixture into another small bowl; stir in sour cream. Refrigerate.

In 9- x 13-inch (3.5 L) baking dish, toss potatoes and onion with 3 tbsp (45 mL) of the herb mixture; season with salt and pepper and arrange in even layer. In small baking dish, toss beets with 1 tbsp (15 mL) of the herb mixture; cover with foil. Place baking dishes, side-by-side in 425°F (220°C) oven. Bake until tender, about 50 minutes, tossing potatoes occasionally. Keep warm.

In medium bowl, toss mushrooms with 2 tbsp (25 mL) of the herb mixture; thread onto metal skewers. Season chops with salt and pepper. Place skewers and chops on greased grill over medium-high heat. Grill, covered, turning twice, for 12 minutes or until chops reach internal temperature of 145°F (73°C) for medium-rare. Brush chops with remaining herb mixture during the last 2 minutes of grilling. Rest for 5 minutes.

Cut lettuce into quarters, keeping base intact. Brush cut sides of lettuce with remaining oil. Turn off heat, grill lettuce over remaining heat just until grill marked, 1 to 2 minutes. Arrange lettuce, chops and skewers on large board. Sprinkle with cheese and parsley. Serve potatoes, onions and beets on the side with sour cream sauce.