I recently had a similar cocktail at the Ravenous Pig in Orlando, Florida (wonderful experience there). I found several recipes for bacon-infused bourbon online, but decided to try it with rye as I prefer that spirit for Old Fashioned cocktails.
I picked a happy medium of the recipes I found for the amount of bacon drippings to use (from 1 oz. fat to 750 ml liquor, to 1 cup fat to 2 cups liquor {at Restaurant August}). I used about 1/4 cup of my homemade bacon (using the MC cure) drippings that I had saved in the refrigerator with 750 ml Old Overholt Straight Rye whiskey.
You add the liquor to the melted fat and agitate the jar frequently over 6 hours, warming as needed to keep the fat liquid; then freeze overnight to solidify the fat for removal.
The recipe for the infusion and cocktail that I found on the New York Magazine site called for maple syrup which was also listed as an ingredient in the Ravenous Pig menu. I was so happy I already had some maple syrup on hand.
The Ravenous Pig used the maple glazed bacon strip garnish. I wanted to use that idea, but I didn’t want to take 20 minutes to cook up just a couple of slices of my homemade bacon so I (gasp!) used my “emergency freezer bacon” – Hormel Microwave Ready bacon that I keep in the freezer for bacon emergencies (anyway, it’s still BACON). This was very easy to do and I think the cocktail is very good.