Start by slicing the bell peppers into thin strips and the onion into half-moons, setting them aside for quick addition later.
Cut the chicken breasts into thin strips, then toss them in a bowl with fajita seasoning until evenly coated.
Heat your skillet over medium-high heat until shimmering, then add olive oil, swirling to coat the bottom.
Add the seasoned chicken strips in a single layer to the hot skillet. Sear without moving for 2-3 minutes until golden brown on one side, then flip and cook another 2-3 minutes until cooked through and slightly caramelized.
Remove the cooked chicken and set aside. In the same skillet, add the sliced peppers and onions. Cook for 5-7 minutes, stirring occasionally, until the peppers blister and the onions soften, filling your kitchen with a smoky aroma.
Return the chicken to the skillet and toss everything together, letting the flavors mingle for 1-2 minutes. The peppers should be charred at the edges, and the chicken juicy and tender.
Squeeze fresh lime juice over the skillet mixture, then give it a gentle toss. This brightens the dish and balances the smoky flavors. Taste and adjust seasoning if needed.
Turn off the heat and let the skillet sit for a minute. Serve hot, garnished with cilantro, sour cream, or shredded cheese if desired, and squeeze a little more lime for that perfect zing.
