Preheat oven to 450°. Line a baking sheet with parchment paper.
Cut baguette on a diagonal into ½-inch-thick slices. Place slices on prepared pan. Using 2 tablespoons olive oil, brush each side of bread evenly. Bake until lightly crisp and golden, 3 to 5 minutes. Let cool for at least 10 minutes.
Reduce oven to 375°. Line a separate baking sheet with parchment paper.
Peel rutabaga and cut in half. Slice rutabaga into ⅛-inch-thick slices, and quarter each slice.
Place rutabaga in a large bowl. Add garlic, thyme, ¼ teaspoon pepper, salt, and remaining 2 tablespoons olive oil. Toss to coat rutabaga.
Lay slices in a single layer on prepared pan. Bake until rutabaga is golden and tender, 13 to 15 minutes. Let cool completely on pan.
In a small bowl, combine cream cheese, Parmesan, and remaining 1 teaspoon pepper. Spoon mixture into a piping bag fitted with a small round tip.
Pipe cream cheese mixture onto cooled baguette slices as desired. Top with 3 to 4 rutabaga slices. Garnish with thyme leaves, if desired.
Recipe by Victoria at https://victoriamag.com/roasted-rutabaga-crostini/