Start with center cut beef tenderloin about 8-9 inches, often referred to Chateaubriand.
A day or two ahead of time, salt and pepper, wrap and leave in fridge.
Sear beef in hot pan. Brush on dijon mustard. Horsradish as alternative. Let sit and cool.
Duxelle:
This is essentially a mushroom paste that will wrap the beef.
Hot dry pan on low-medium heat
Mushrooms (700g or around 24oz package from Costco)
Few garlic cloves, chopped or minced
Handful of Chestnuts (or walnuts)
Salt/Pepper
Blitz in food processor until its a fine minced paste, but don't liquefy.
Move mixture to pan and stir every few minutes. The goal here is to dry out the paste so do not cover. Let it bubble on the store allow the moisture to escape. It's ok that it's dry, this mixture will absorb some of the moisture from the beef. Add fresh Thyme to kick it up a notch.
Assemble:
Lay out cling wrap and moisten with a rag. Lay out parma ham, enough that will wrap completely around tenderloin. Next, smear paste on top of ham in what should about cover all of the beef when you roll it over.
Put beef in middle, roll ham and mixture over beef letting cling wrap do the work. Make it tight as possible, slowly rolling and tucking the mixture around the beef. Tie up ends as tight as possible. Trim any access off the ends or your first slice from each end will be all pastry.
Put in fridge until ready
Egg yolk wash
425 until internal temp reaches desired temp 130 for me.
Alternative, consider Sous Vide for next time.
