1 pound russet potatoes, peeled and thinly sliced
1 pound sweet potatoes, peeled and thinly sliced
1 1/3 cups heavy cream
3 tablespoons butter
1 garlic clove, minced
1/2 teaspoon dried rosemary
1/2 teaspoon dried thyme
1 teaspoon kosher salt
1/2 teaspoon black pepper
1 cup sharp cheddar cheese, grated