Ukrainian treasure chest (pierogi stuffed tenderloin)

Directions

1. Pat the tenderloins dry with a paper towel. Use a thin blade knife to remove the silver skin and then make a cut lengthwise into the thickest part of the “head” to butterfly the tenderloin. The cut should go nearly but not all the way through in order to open up the surface area. Make a series of four to six cuts from head to “tail” through the thick parts to open like a book. Lay the butterflied tenderloin inside a cut-open resealable bag and hammer gently with a meat tenderizer until even in thickness.
2. Sauté the bacon and onion together in a sauté pan over medium heat, cooking until the onions are soft, about seven minutes (the bacon will not be crisp). Set aside to cool.
3. Cook the perogies in a large pot of boiling, salted water until they float (follow the package instructions for timing). Drain them in a colander, toss with the cooked bacon and onion, then cool to room temperature.
4. Preheat the oven to 350 °F (180 °C).
5. Lay one of the flattened tenderloins on a cutting board and spoon the cooled perogies on top, covering the meat but not quite to the edges. Place the second tenderloin on top in the opposite way, so that the wide end of the bottom tenderloin meets the narrow end of the top one. Form into a cylinder (the cooled perogies will help hold the cylindrical shape) and tie the roast with four to six pieces of butcher’s twine.
6. Season the roast with salt and pepper and place on a rack in a roasting pan . Cook uncovered for 35-40 minutes until the middle of the stuffing reaches 145°F then remove to rest on a cutting board. Remove the butcher’s twine and slice the tenderloin roast, into thick slices and serve with the sour cream and green onions. 

Recipe from Michael Olson’s book, “Living High Off The Hog” Random House (2019).