Making In-N-Out Burgers At Home | But Better

Burger Buns:

1. Heat the milk to 98℉ (37℃). Stir in the yeast and let sit at room temperature for 10 minutes.
2. In a medium bowl whisk together 2.25 cups (320g) flour, salt, and sugar. Transfer that mixture to the bowl of a stand mixer and set aside. 
3. In a small saucepan over medium heat whisk together the remaining 2 Tbsp (20g) bread flour and water. Continue to cook and whisk the roux until it thickens into a paste and you can see lines left behind in the roux from the whisk. Remove to a bowl and let cool to room temperature. 
4. Fit the stand mixer with a dough hook. With the mixer running on low, pour in the bloomed yeast mixture followed by 1 egg, the egg yolk and the cooled roux. Mix for 3-5 minutes or until the dough becomes smooth and doesn’t stick to the sides of the bowl too much. 
5. Add in the softened butter, 1 Tbsp at a time, and mix for 2-3 minutes or until all the butter is evenly incorporated and the dough is very smooth. Remove the dough from the stand mixer and shape it into a light ball. 
6. Lightly grease a large bowl with cooking spray and place the dough ball inside. Cover with lightly greased plastic wrap and let rise at room temperature until doubled in size, about 1.5 - 2 hours.
7. Once the dough has risen, punch down the dough and place on a lightly floured work surface. Divide the dough into 6 equal portions, each one should weigh between 95 and 105 grams. 
8. To shape the dough take the edges and stretch and fold them towards the center. Turn the dough over, so it is seam side down, and place it on a part of the work surface that doesn’t have flour. Cup your palm over the top of the dough. Move your hand and the dough in a circular motion, keeping constant contact with the work surface, to form the dough into a taut ball. Repeat with the other pieces of dough. Place the balls on  parchment lined baking sheets, 3 per baking sheet. 
9. Cover the buns with a damp towel or inverted baking sheet and let proof in a warm area for 45 minutes.
10.  While the buns are proofing preheat the oven to 400℉ (205℃). 
11.  Whisk the remaining egg and a splash of water together and gently brush this on top of the buns. 
12.  Bake for 15-17 minutes or until golden brown on top. Immediately brush the tops with melted butter and set aside until ready to serve. 

‍Burger Sauce:

1. Melt the butter in a medium saucepan over medium heat. Add the onions, sugar, and a pinch of salt and cook, stirring occasionally, for 30 minutes or until the onions are deeply caramelized. If the pan gets too dry or the onions start to cook too fast add a splash of water and turn down the heat slightly. 
2. In a medium bowl, whisk together the mayo, ketchup, chives, Worcestershire sauce, pickles and caramelized onions. Season to taste with salt. Set aside. 

‍Burgers:

1. Cut the onion, through the skin, into 1/2” (12mm) rounds. Remove the skin and then leave the onion as a whole round (don’t separate it into rings). 
2. Heat a medium skillet over medium-high heat and add enough oil to coat the bottom of the pan. Once the oil is hot, add the onion rounds and sear for about 3 minutes, pressing them down with a press if you have it, or until the onions are deeply caramelized on the first side. Flip the onions, it's ok if they don’t hold together at this point, and sear on the second side. Add 2 Tbsp butter to the pan, if you’d like, to baste the onions with. Season the with salt to taste and then set aside. 
3. Melt 1 Tbsp of butter in a medium skillet over medium heat. Cut the burger buns in half and toast in the melted butter until golden brown. Remove to a plate. 
4. Divide the ground beef into 4 even pieces. Form each piece into a ball. 
5. Heat a cast iron pan over medium-high heat. Brush the pan with some of the oil to coat. Once the oil starts to smoke add one of the burger balls to one side of the pan. Use a metal spatula to help flatten into a burger patty that is about 4” (10cm) in diameter. Repeat with a second piece of meat. Season the patties generously with salt. Sear the burgers for 2-3 minutes or until a rich, caramelized crust forms. Flip over and season the other side generously with salt. Add a garlic clove, half of the thyme and 2 Tbsp butter. Let the butter melt and then baste the burgers until they are seared on the other side. Remove the burgers to a baking sheet, wipe out the pan and then repeat with the remaining two burgers. 
6. Once all four of the burger patties are cooked, wipe out the pan of the excess butter and remove the garlic and thyme. Add all the burger patties back to the pan and top 2 of the burgers with a slice of cheddar cheese and 2 of the burgers with a slice of muenster cheese. Add a splash of water to the pan and cover with a lid to melt the cheese. 
7. Remove the lid and add a griddled onion round to the top of both patties with cheddar cheese. Add the patty with the munster cheese on top of the griddled onions. 
8. To build the burgers, add a heaping tablespoon of burger sauce to the top and bottom buns and spread it out to the edges. Top the bottom bun with the seasoned tomato slice, followed by a piece of iceberg lettuce, and then the stack of burger patties. Finish with the top bun and repeat making the rest of the burgers. Serve immediately.