Step 1

Heat grill to 425°F. Clean grill grates.

Step 2

In a small bowl mix together the ancho, chipotle, garlic powders and kosher salt.

Step 3

Using a sharp knife, clean any fat and sinew off the tenderloin, discard.

Step 4

Carefully slice the pork tenderloin down the middle, but not completely through, opening it like a book. This is the butterfly technique. Spread out flat and rub spice mixture on both sides. Allow to rest while grill heats up.

Step 5

Oil the grill and cook pork for 12 minutes, turning half way through. Baste with any BBQ sauce, if desired, before turning and again on other side. Meat should be cooked with an internal temperature at 135°-145°F. Let rest 5 minutes and slice.