Preheat your oven to 350°F (175°C) and grease a meatloaf pan with olive oil or cooking spray.

In a skillet over medium heat, add olive oil and sauté the finely chopped onion until translucent, about 5 minutes, then add minced garlic and cook for another minute.

In a large mixing bowl, combine ground chicken, parsley, egg, pepper, and salt, then mix in the cooled onion and garlic mixture.

Spread the meat mixture into a ¾ inch thick rectangle on parchment paper.

Layer the deli ham and then the Swiss cheese evenly over the meat mixture.

Roll the meat mixture tightly into a log using the parchment paper and place it seam-side down in the prepared pan.

In a small bowl, whisk the melted butter, vinegar, mustard, and sugar substitute together and brush it generously over the meatloaf.

Bake in the preheated oven for 1 hour and 20 minutes until the internal temperature reaches 165°F (74°C).

Let the meatloaf rest for about 10 minutes before slicing.