1. Begin by placing potatoes in a large saucepan and cover with water, add about 4 Tbsp of salt. Bring the water to a boil over medium-high heat and boil for about 10 minutes until tender.
2. While potatoes are boiling, cook bacon over medium-high heat in a large non-stick frying pan for about six minutes, until crispy and golden brown. Transfer bacon to a plate lined with paper towels.
3. In a small sauce pan, bring the chicken stock to simmer over high heat. Add shallots, cornichons, and capers. Reduce the heat to medium-low and simmer gently for 2 to 3 minutes, remove from heat and set aside.
4. Drain the potatoes in a colander and release any excess moisture. Transfer potatoes to a large serving bowl.
5. Add about one-third of the broth mixture to the bowl and gently fold into the potatoes. Repeat two more times stirring and folding until the potatoes start to slightly break apart.
6. Add the bacon and parsley and fold in until combined; add the mayonnaise and fold in until combined. Taste and season with salt and black pepper.

Serve warm, at ambient temperature, or chilled.