In a large Dutch oven over medium heat, cook diced bacon until crispy, about 5-7 minutes. Remove the bacon from the pot and set aside, reserving the rendered fat.

In a mixing bowl, combine all-purpose flour, baking powder, kosher salt, freshly cracked pepper, and minced chives. In a separate bowl, whisk together the reserved bacon fat, sour cream, and whole milk until smooth. Fold the wet ingredients into the dry ingredients gently until just combined.

Return the Dutch oven to medium heat and melt unsalted butter in the reserved bacon fat. Add diced onion, carrots, leek, and celery, and sauté for 3-4 minutes.

Stir in dried rubbed sage and dried thyme, cooking for another minute. Then, sprinkle in the flour and cook for an additional 2-3 minutes, stirring continuously.

Slowly incorporate chicken stock into the mixture, stirring to avoid lumps. Bring the mixture to a gentle simmer for about 5 minutes.

Add shredded cooked chicken, heavy cream, and the crisp bacon back to the pot.

Using a cookie scoop, drop spoonfuls of dumpling batter over the simmering soup. Cover the pot with a lid and let it simmer for 15-17 minutes.

Serve hot in bowls, garnished with additional fresh chives if desired.