To make the rub: using a spice grinder or mortar and pestle, crush the peppercorns; place in a small bowl and thoroughly mix with the rest of the rub ingredients.
To make the sauce: in a small saucepan, whisk together all the sauce ingredients with ¼ water; simmer over low heat for about 10 minutes, stirring occasionally, to allow the sugar to fully dissolve and all of the flavors to blend; set aside while you grill the steaks.
Allow steaks to stand a room temperature for 20-30 minutes before grilling.
Press the rub into both sides of the steaks; lightly brush or spray both sides of the steaks with the olive oil.
Grill over direct high heat until the internal temperature reaches 145° for medium rare, 8-10 minutes, turning once halfway through grilling time.
Remove from the grill and allow to rest for about 5 minutes.