Steps
Season chicken thigh with salt and pepper.
Heat olive oil in a skillet over medium heat. Brown the chicken on both sides, about 6 minutes total. Remove and set aside.
In the same skillet, sauté red onion, aji amarillo, and garlic until fragrant and soft, about 3 minutes.
Stir in cumin and mustard, cook 30 seconds more.
Add vinegar and chicken broth, scraping any browned bits from the pan.
Return chicken to pan, cover, and simmer on low for 10 minutes, flipping halfway through.
Let the chicken cool to room temperature in the sauce to absorb flavors.
Serve topped with olives, boiled egg halves, and fresh cilantro.