Celery Root and Parsnip Puree

Combine celery root, parsnips, and potato in large saucepan; add enough water to cover. Sprinkle generously with coarse salt. Bring to boil. Reduce heat to medium; cook until vegetables are very tender when pierced with sharp knife, about 20 minutes. Drain well. Return vegetables to pan and place over medium heat, stirring constantly until moisture evaporates, 2 to 3 minutes. Working in batches if necessary, spoon vegetables into potato ricer; press into microwave-safe medium bowl. Add warm half and half and pink-peppercorn butter, if desired. mash until smooth. Season with coarse salt and black pepper. DO AHEAD: Can be made 1 hour ahead. Rewarm in microwave until heated through.