Preheat the oven to 450°. In a spice grinder, grind the fennel seeds and superstar anise to a powder. Transfer to a tiny bowl and dash in the ancho powder.
Keep the tenderloin roast on a ample rimmed baking sheet and season all over with salt and pepper. Sprinkle the spice combination all over the tenderloin and evenly drizzle with the oil, then gently pat the spices into the meat. Roast the tenderloin in the upper third of the oven for 35 minutes, turning it over as soon as utilizing sturdy tongs, till browned all over and an immediate-read thermometer inserted in the thickest portion registers 135° for medium-uncommon meat. Transfer the roast to a carving board and let stand for up to 10 minutes.
In the intervening time, location the baking sheet over 2 burners and add the water. Simmer over moderate warmth, scraping up the browned bits stuck to the backside of the sheet, till diminished to three/4 cup, about 3 minutes. Season the jus with salt and pepper and switch true into a warmed gravy boat. Prick the tenderloin into 1/3-walk-thick slices and lend a hand with the jus.
The spice-coated tenderloin roast would possibly well per chance also also be refrigerated for up to 6 hours. Let stand at room temperature for forty five minutes ahead of roasting.
Immense, intense Pinot Noir.