Combine all the spices in a bowl and mix well.
Prepare the tri tip by cutting off any excess fat or any silvercap.
Rub the roast liberally with the spice mixture and place in a plastic bag suitable for sous vide cooking. Refrigerate for 12-24 hours.
Set your sous vide cooker to 132-135°F and 6-8 hours.
Remove all the air from the plastic bag and submerge.
Cook for 6-8 hours as desired.
Toward the end, fire up your grill.
Remove the cooked tri tip from the bag and reserve the juices.
Oil grill grates and cook tri tip on each side for 2-3 minutes.
Remove and let rest 10 minutes before carving against the grain.
Serve with the jus.