In a shallow pan lightly colour the beef trimmings in the oil, add the shallots and sweat for three minutes without colour. Next add the mushrooms, cook down, then add the wine. Reduce to a quater and then add the rest of the ingredients. Bring to the boil, reduce to a simmer and cook out for 1 hour. Pass through a sieve and reduce to sauce consistency, season with salt and pepper and sugar if too acidic.

In a saucepan sweat the onion, celery and salt with the butter, add the milk, chicken bouillon and water then the celeriac and pepper. Bring to a boil and reduce to simmer. Cook for 30 minutes and then allow to cool. Pass off through a colander and then place into a food processor and blend until very fine puree.

Season beef fillets and sear in some butter until nicely coloured on each side in a thick bottomed pan. Place into a pre-heated oven and cook as required. Remove from the oven and rest for 10 minutes.

Reheat the celeriac puree and place a spoonful on to the plate, then place the fillet steak on top and carefully add the sauce.