Burger Bun:

1. In a small saucepan, whisk together 2 Tbsp (20g) bread flour, water and 4 Tbsp (60g) whole milk. Heat over medium and stir constantly until a thick, sticky paste, called a tangzhong, forms. Scrape the tangzhong from the pan into a small bowl and set aside to cool to room temperature. 
2. In a microwave safe bowl heat the remaining ½ cup (120g) of whole milk to 95℉ (35℃). 
3. Whisk the yeast into the warmed milk and let sit at room temperature for 10 minutes. 
4. In the bowl of a stand mixer fitted with the dough hook attachment, add the remaining 2.5 cups (320g) of bread flour, sugar and salt. Whisk to combine. 
5. Adhere the bowl to the stand mixer. With the mixer on medium-low speed, add 1 egg plus the yolk followed by the yeasty-milk and the tangzhong. Continue to mix until a dough forms (if the dough appears dry, add another tablespoon of milk to hydrate.). Knead for 4 minutes until the dough is smooth and elastic. 
6. Add the softened butter in approximate 1 Tbsp increments, mixing to incorporate before adding the next. Once all the butter is incorporated, knead for 1-2 minutes. 
7. Turn the dough out onto a work surface and roll into a smooth, taut ball. 
8. Lightly grease a large bowl with vegetable oil and place the dough into the bowl. Cover with plastic wrap and set aside at room temperature to rise for 1-2 hours or until doubled in size. 
9. Line a baking sheet with parchment paper and set aside. 
10. Punch down the dough, releasing the gasses, and turn the dough out onto a lightly-floured work surface. 
11. Divide the dough into six even pieces (each weighing around 95–105 grams) and form each into a ball by pulling and stretching the sides of the dough into the center. Flip it over so the seam-side faces down and roll it in circles with your hand, maintaining contact with the work surface, until you form a tight, smooth, round ball. 
12. Transfer the ball of dough to the prepared, parchment-lined baking sheet and repeat with the remaining balls of dough, making sure to space them 2.5” (6cm) apart.
13. Cover with an inverted baking sheet, or with greased plastic wrap, and set aside at room temperature to proof for 30 minutes. 
14. In a small bowl whisk together the remaining egg and a splash of water until homogenous. 
15. Before baking, brush egg wash all over the top and sides of each bun. 
16. Bake at 375℉ (190℃) for 15-18 minutes until golden brown.
17. Remove from the oven and brush each with melted butter. Transfer to a cooling rack and set aside to cool to room temperature. 
18. When ready to serve, in a medium skillet over medium heat, add butter to melt. Place a halved burger bun, cut-side-down, into the melted butter to toast until golden brown.

Black Garlic and Chive Mayo:

1. Into a small mixing bowl, whisk together the mayonnaise, chives, black garlic paste, salt and pepper to taste, and a splash of black vinegar. Taste and adjust seasoning, as needed. 
2. Refrigerate until ready to use. 

Beef Patty:

1. Add the beef to a large bowl and toss to evenly combine. 
2. Pass the meat through an electric meat grinder into a large bowl.
3. Shape the beef into ¼ lb (113g), square patties (you’ll use 2 patties for each burger) that coincide with the dimensions of the bun and season both sides with salt, and any other desired spices.
4. Pre-heat a medium cast iron skillet over medium heat until sizzling hot. 
5. Add the seasoned patties to the hot skillet and increase the heat to medium-high. Sear for 2-3 minutes until very crispy. Flip and place a slice of cheddar and smoked provolone cheese on top of each patty, to melt. 
6. Add a splash of water into the hot skillet then loosely cover with a sheet of aluminum foil, allowing the steam to melt the cheese.
7. Remove the pan from the heat and assemble the burger. 

Assembly:

1. Spread a generous spoonful of the black garlic chive mayo onto the toasted bottom bun followed by a squirt of ketchup. 
2. Place a cheesy patty on top.
3. Add 2-3 slices of cooked bacon.
4. Top with the second cheesy patty and another 2-3 slices of bacon.
5. Add a spoonful of black garlic chive mayo on top of the bacon and another squirt of ketchup.
6. Crown with the toasted top bun. Repeat making the remaining Baconators. Serve immediately.