Preheat your oven to 400°F and line a baking sheet with parchment paper for easy cleanup.
Dice the red potato into small, uniform cubes to ensure even roasting.
In a small bowl, whisk together the olive oil, lime juice, lime zest, chili powder, garlic powder, salt, and pepper.
Toss the potato cubes with half of the chili-lime marinade and spread them on the baking sheet.
Roast the potatoes for 20-25 minutes until they are golden and tender.
While potatoes roast, coat the chicken breast with the remaining marinade.
Heat a cast-iron skillet over medium-high heat and sear the chicken for 6-7 minutes per side until smoky and fully cooked.
Let the chicken rest for 5 minutes before slicing, then serve alongside the roasted potatoes and garnish with fresh cilantro.