Potato Carrot Gratin - Challenge Dairy

Ingredients

• 3 Tablespoons Challenge Butter, softened, divided
• 2 ¼ cups heavy cream
• 1 shallot, quartered
• 2 garlic cloves, smashed and peeled
• 6 sprigs fresh thyme
• 1 Tablespoon fresh rosemary
• kosher salt and freshly ground black pepper
• ½ pound carrots, peeled and thinly sliced into coins
• 2 pounds Yukon gold potatoes, peeled and thinly sliced
• ¾ cup grated parmesan