Pat the tri-tip roast dry
Trim excess fat if needed
Season generously with salt, pepper, and desired spices
Let the roast sit at room temperature for 30 to 60 minutes
Preheat oven to 425°F
Heat a skillet over high heat with a little oil
Sear the tri-tip on all sides until browned
Transfer the roast to a roasting pan or oven-safe skillet
Insert a meat thermometer into the thickest part
Roast in the oven until the internal temperature reaches 130°F for medium-rare or 140°F for medium
Remove from the oven and rest for 10 to 15 minutes
Slice thinly against the grain
Serve immediately