Preheat the oven to 350 degrees. Line a sheet pan with parchment paper. Set aside.
In the bowl of a stand mixer, combine the sausage and shredded cheese. Mix until incorporated. Add the baking mix, garlic powder, pepper, and chives, and mix again. If the mixture seems to dry to hold together, add milk - one tablespoon at a time - until the mixture comes together.
Using a tablespoon-sized scoop, portion the mixture out and roll into balls. Place on the prepared baking sheet.
Bake for 20 minutes until golden brown and the internal temperature has reached 160 degrees.
Meanwhile, add the sour cream and horseradish to a small bowl and stir to combine. Season with salt and pepper.