In a small bowl combine chili powder, paprika, cumin, 1/2 teaspoon of the salt, black pepper and cayenne pepper. Set aside.

In a medium skillet, heat oil over medium heat.

Add bell pepper, onion and mushrooms, and cook until tender, about 5 to 7 minutes.

Add garlic and cook until fragrant, 1 minute.

Season with remaining 1/2 teaspoon salt and remove from heat.

Prepare a grill for medium-high heat cooking.

Open butterflied tenderloins and season all sides with spice mixture.

Stuff 1 tenderloin with half of the vegetable mixture and fold over.

Repeat with remaining tenderloin.

Using butcher’s twine, tie every 2 inches to prevent stuffing from falling out while grilling.

Place tenderloins on the grill and cook, rotating every 2 to 3 minutes to prevent burning, until cooked through, about 15 minutes.

Remove from the grill when pork reaches an internal temperature of 145°F.

Allow to cool for 5 minutes.

Remove butcher’s twine and slice.

*Slice tenderloin lengthwise 3/4 of the way through and open like a book or ask your butcher to do it for you.