In a large mixing bowl, combine ground beef, chopped onions, bourbon, minced garlic, egg, Worcheshire Sauce, steak seasoning, and milk; mix well until well combined, then fold in the bread crumbs, and mix well, until well combined.
Spray your mini loaf pan with nonstick cooking spray, or brush with olive oil, and add your meatloaf mixture; if you do not have mini loaf pans, place a piece of parchment paper in the air fryer basket and then make a meatloaf loaf shape, onto the of the parchment paper.
Place the mini loaf pans into the air fryer basket and cook for 20 minutes at 350 degrees F, using the air fryer setting.
Add the ketchup, brown sugar, and bourbon in a large bowl, mix until well combined, then brush with a pastry brush onto the meatloaf. Cook for another 3-5 minutes or until the internal temperature reaches 160 degrees F.
Remove the meatloaf from the baking dish, place it on a serving platter, and let it cool for a few minutes. Serve with additional Bourbon Sauce.