Heat a large dutch oven over medium-low heat and add the bacon. Cook until the fat is started to render and a few pieces of the bacon are crispy. Stir in the onion, paprika, salt and pepper and cook for 5 minutes. Stir in the brown sugar and cook for another minute or so.
Stream in 3/4 cup bourbon and 1/2 cup of chicken stock, stirring with a wooden spoon to release any bits of flavor from the bottom of the pot. Simmer the mixture, stirring occasionally, for about 10 minutes until the liquid has evaporated and the mixture has thickened. Stir in the remaining bourbon and 1 cup of stock, cooking again for 10 more minutes while stirring, until that liquid has evaporated too. Add the last of the chicken stock.
Transfer the mixture to a blender and very carefully, blend until pureed. (I put a towel over the top and hold it down.)
Return the mixture to the same pot and cook for another 10 minutes until it has cooked down a bit more and thickened. Taste and add more salt and pepper if needed. Stir in the butter. Let cool completely before scooping into an airtight container and storing in the fridge. I like