Step 2: Make the Baconnaise
While the bacon is cooking, prepare the baconnaise. In a small bowl, combine the mayonnaise, Dijon mustard, and crumbled bacon. Mix until well combined. The mustard adds a tangy touch that balances the richness of the mayo and the smokiness of the bacon. Adjust the flavors to your liking by adding more mustard or bacon if desired. Set aside for later.
Step 3: Prepare the Patties
Divide the ground beef into four equal portions, each weighing about 4 ounces. Gently roll each portion into a ball, being careful not to overwork the meat to maintain a light and airy texture.
Step 4: Cook the Smash Burgers
Heat a cast-iron skillet or griddle over medium-high heat. Once hot, place the beef balls on the skillet. Using a sturdy spatula, press down on each ball to flatten it. This creates the signature crispy, caramelized edge that makes smash burgers unique. Cook for 2-3 minutes without moving them, seasoning with salt and pepper. Once the edges are crispy, flip the patties and cook for another 1-2 minutes. If using cheese, add a slice during the last minute of cooking to allow it to melt.
Step 5: Assemble the Burgers
While the patties are cooking, toast your burger buns in the same skillet or a separate pan until golden brown. To assemble, spread a generous amount of baconnaise on the bottom of each toasted bun, place the freshly cooked patty on top, and add any additional toppings like lettuce, tomatoes, or pickles before closing with the top bun.
