Cut the chicken into narrow strips. Season with salt, pepper, half the cumin and smoked paprika, drizzle with a tablespoon of vegetable oil and a teaspoon of lime juice, mix, set aside for at least half an hour to marinate.
Cut the bell pepper into strips, the onion into wider half-slices, mix thoroughly with salt, pepper, the rest of the cumin and smoked paprika, a tablespoon of oil and lime juice.
Heat a grill pan (or any other pan you have), place the chicken pieces and grill (over higher heat, about 3 minutes on each side), set aside on a plate.
On the same pan add the vegetables, reduce the heat slightly and fry thoroughly, stirring occasionally, for a total of about 6 - 7 minutes. Add the chicken and mix gently. Sprinkle with chopped pickled jalapeño pepper.