Preheat oven to 350 F, generously grease a meatloaf pan, set aside.

Cook onions in olive oil until soft and translucent. Add garlic, cook for another minute or so. Remove from heat and allow to cool slightly.

In a large bowl, mix together chicken, parsley, egg, pepper, and salt. Add onion and garlic, mix well to combine.

Spread chicken out onto a sheet of parchment paper. I like to aim for the length of my loaf pan (8"), by however long it ends up, when spread to about ¾" thick.

Lay out the ham slices to cover the chicken - leaving 1" uncovered, across each of the short sides.

Top with Swiss cheese slices.

Starting with one of the short ends, roll up the meatloaf along the length of it - the parchment paper will help with this.

Be sure to pick up the paper on the end you’re rolling, going kind of up and over, rather than a straight roll. You want to keep the filling in, not push it.

Transfer meatloaf to the prepared pan, seam side down.

Whisk together melted butter, vinegar, mustard, and sugar substitute, brush over meatloaf.

Bake for 1 hour 20 minutes, or until a meat thermometer measures the internal temperature at 165 F.