Preheat your oven to 400°F (200°C).
Dice the chicken breast and yellow potato into small, uniform 1/2-inch cubes.
In a bowl, toss the chicken and potatoes with 0.5 tsp of olive oil, sea salt, black pepper, thyme, and rosemary.
Spread the mixture onto a parchment-lined baking sheet and roast for 18-20 minutes until the chicken is cooked through and potatoes are golden.
While roasting, heat the remaining 0.5 tsp of olive oil in a large skillet over medium heat.
Add the diced carrots, celery, and onion to the skillet, sautéing for 6-8 minutes until tender and fragrant.
In a small jar or bowl, whisk the arrowroot powder into the cold chicken broth until no lumps remain.
Pour the broth mixture and the coconut milk into the skillet with the sautéed vegetables.
Simmer the sauce for 3-5 minutes, stirring constantly, until it thickens into a rich, velvety gravy.
Fold in the frozen peas and the roasted chicken and potato mixture, stirring for 1 minute to heat through.
Transfer the mixture to a serving bowl and enjoy immediately while hot.