In medium bowl, mix ground beef, garlic, chili powder, ketchup, and eggs. Add salt and pepper to taste. Shape into patties about four inches wide, and set aside.

Prepare the stuffing: Heat oil in a sauté pan over medium heat. Add onions and mushrooms and sauté until onions are translucent and mushrooms are golden brown, about 15 minutes. Season with salt, garlic powder, and black pepper.

Gently press your thumb halfway into each burger to form an indentation. Stuff the patties with one heaping tablespoon mushroom and onion mixture. Shape the meat around the stuffing and transfer to a baking sheet. Broil for 20 minutes.

Serve burger inside a bun and topped with Bourbon Barbecue Sauce (recipe follows).

Heat oil in a large saucepan over medium heat.

Add onion and cook, stirring occasionally, until tender, about two to four minutes. Add garlic and jalapeño and cook, stirring occasionally, until fragrant.

Add bourbon, increase heat to high, and bring to a boil. Cook until most of the liquid has evaporated, about five minutes.

Stir in blueberries, cayenne pepper, chili powder, ketchup, vinegar, brown sugar, molasses, and allspice. Return to a boil. Reduce the heat and simmer, stirring occasionally, until thickened, about 10 to 15 minutes.

Using an immersion blender or a standard blender, blend the sauce until smooth.