Carrot and Parsnip Fettuccine

Name: Carrot and Parsnip Fettuccine
Ingredients: 3/4 pound carrots, peeled and trimmed; 1/2 pound parsnip, peeled and trimmed; 3 tablespoons unsalted butter; 1 tablespoon olive oil; a few swipes of fresh nutmeg on the microplane grater; pinch of white pepper; 2 tablespoons heavy cream (optional); 2 sprigs fresh thyme; sea salt