Cut bacon strips in half lengthwise, then cut each thin strip into 3 equal sections for a total of 48 pieces. Set aside.
Mix soy sauce and honey in a medium mixing bowl. Add water chestnuts and turn to coat. Marinate at room temperature for approximately 30 minutes, turning water chestnuts 2-3 times during that time.
Preheat the oven to 400°F and place a metal rack inside a large, rimmed baking sheet. Spray rack with non-stick cooking spray and set aside.
Drain water chestnuts but reserve the marinade. Wrap each water chestnut with a piece of bacon, then repeat with a second strip on the opposite side. Secure both pieces of bacon with a toothpick and place on the baking rack.
Repeat with remaining water chestnuts. Brush each appetizer with reserved marinade on all sides. Place the prepared baking sheet in a preheated oven for 20 minutes, then remove from the oven and brush with more marinade before returning to the oven for another 10-15 minutes.
While the water chestnuts are roasting, combine Greek yogurt, Dijon mustard, hot sauce, cayenne pepper, and parsley in a small bowl. Season salt and black pepper, to taste. Cover and place in the refrigerator until ready to serve.
When finished, remove the bacon-wrapped water chestnuts from the oven and serve immediately with the spicy mustard sauce for dipping. Enjoy!