Inspired by Chef Thomas Keller's iconic Hen Egg dish at Per Se, this recipe brings the luxurious experience of a slow-cooked egg, velvety potato puree, and crispy pancetta to your home kitchen.
**For the Pancetta:** Place the diced pancetta in a cold small skillet over medium-low heat. Cook slowly, stirring occasionally, until deeply golden brown and crispy, about 8-10 minutes. Remove the crispy pancetta with a slotted spoon and place it on a paper towel-lined plate to drain. Reserve the rendered fat if desired for other uses, or discard.
**For the Potato Puree:** Place the peeled and cut potatoes in a medium saucepan. Cover with cold water and add a generous pinch of salt. Bring to a boil over high heat, then reduce to a simmer and cook until fork-tender, about 15-20 minutes. Drain the potatoes thoroughly in a colander.
Return the hot, drained potatoes to the dry saucepan over very low heat for 1 minute, stirring, to evaporate any remaining moisture. Add 3 tablespoons of butter, the heavy cream, and whole milk. Mash the potatoes with a potato masher or rice them directly into the pot. For an extra silky puree, pass the mixture through a fine-mesh sieve or use an immersion blender until completely smooth. Season generously with salt and white pepper to taste. Keep warm over very low heat, stirring occasionally, or cover until ready to serve.
**For the '63-Degree' Eggs:** Fill a medium pot with water. Place a digital thermometer in the water and heat it gently over low to medium-low heat until the temperature reaches and stabilizes at 145°F (63°C). This is the most crucial step – precise temperature control is key. Adjust the heat as needed to maintain this temperature, stirring the water occasionally to ensure even heating.
Carefully lower 2 of the fresh eggs (still in their shells) into the 145°F (63°C) water. Maintain the temperature as consistently as possible for exactly 45 minutes. (If you prefer a slightly firmer white, you can go up to 60 minutes, but 45 minutes yields a perfect custardy white and runny yolk.)
Once the eggs are cooked, immediately remove them from the water. Crack each egg very gently into a small bowl. The white will be very delicate and barely set, with a warm, flowing yolk.
**To Assemble:** Divide the warm potato puree evenly between two serving bowls. Create a small well in the center of each puree. Carefully slide one slow-cooked egg into the well of each bowl. Sprinkle generously with the crispy pancetta and a pinch of fresh chives. Serve immediately and enjoy the luxurious texture and flavor.