Peel and chop the Yukon Gold potato into 1-inch cubes.
Place the potato cubes in a medium pot, cover with water, and bring to a boil.
Reduce heat and simmer for 12 to 15 minutes until the potatoes are completely fork-tender.
While the potatoes cook, season the chicken breast with half of the sea salt and black pepper.
Heat the extra virgin olive oil in a skillet over medium-high heat.
Sear the chicken breast for 6 to 8 minutes per side until the internal temperature reaches 165 degrees Fahrenheit.
Mince the garlic cloves and finely chop the fresh chives.
Drain the cooked potatoes and return them to the warm pot.
Add the Greek yogurt, minced garlic, remaining sea salt, black pepper, and water to the pot.
Mash the mixture until it reaches a velvety consistency, then stir in the chopped chives.
Slice the chicken and serve it immediately alongside the creamy mashed potatoes.