Fill a pot with water, add the potatoes and stir in 1 teaspoon salt. Set over high heat and bring to a boil. Reduce the heat to a steady simmer and cook the potatoes until fork-tender but not crumbling, around 15 minutes. Drain the potatoes into a colander and set aside to slightly cool.

In a separate skillet, add the bacon and set over medium heat. Cook until golden brown, around 5 minutes. Flip and cook the other side until golden brown and crispy, around 2 more minutes. Transfer the bacon to a plate lined with paper towel and set aside.

Add the anchovies to a large salad bowl and use a fork to mash them into a paste. Add the garlic, egg yolks, lemon juice, mustard, and black pepper and whisk until smooth and combined. While continuously whisking, slowly drizzle in the extra virgin olive oil until fully emulsified. It should be a painfully slow drizzle. Taste the dressing for seasoning and adjust with salt, pepper and lemon juice as desired.

Using your hands, tear each potato in half and add them to the bowl with the dressing. Toss everything to coat. Taste for seasoning and adjust with salt and pepper as desired.

Arrange the lettuce and endive on a large serving platter. Top with the potatoes and crumble the bacon overtop. Garnish with grated Parmigiano Reggiano, if using, and serve while still warm.