I imagine one could make this with almost any root vegetable purée–turnip, carrot, parsnip, potato–or a combination…
1 large or 2 small celeriac heads
6 T butter, divided
salt and pepper, to taste
celery leaves or 1 t celery seeds, optional
4 – 6 eggs
1. Preheat oven to 375ºF. Bring a large pot of (salted) water to the boil. Peel celeriac and cut into wedges. Put into boiling water and cook for 25 minutes, until soft. Drain well. Return to pot along with 4 T butter and mash into a purée. (Or whizz in a food processor). Add salt and pepper. Chop up some celery leaves and stir into mash, or add 1 t celery seeds.
2. Transfer to an oven dish of your choice. Make 4 to 6 indents in the surface of the puree. Break an egg into each indent. Season, if desired, with more salt and pepper and place a small bit of butter on each egg.
3. Bake for 10 to 15 minutes, until the whites are firm, but the eggs are still runny–or however you like your eggs.