Cook bacon according to the directions on the package and save the grease to use for the Bacon Tzatziki Sauce.
Cook Smithfield Roasted Garlic & Cracked Black Pepper Tenderloin according to the directions on the package and slice into long, thin strips.
For the tzatziki sauce peel and grate or finely dice the cucumber and squeeze as much liquid out of it as possible.
Combine the yogurt and leftover bacon grease in a bowl and add the cucumber, diced bacon, garlic, lemon juice, dill, salt and pepper and mix everything together.
Fill each pita with sliced tenderloin, onion, tomato and top with tzatziki sauce and feta cheese.