Cube the chicken breast. In a bowl, add your desired amount of chili oil (start with 1 teaspoon and add more for extra spice!). Sprinkle the chicken with half of the Shin ramen seasoning packet, garlic powder, black pepper, and minced garlic. Toss to coat the chicken well. Let the chicken marinate for at least 10-15 minutes, or up to 30 minutes if you have more time.
Heat a large skillet over medium-high heat. Add the chicken cubes and sear until they are about halfway cooked. This partial cook prepares them for the next step without drying them out.
In a separate pot, bring water to a boil and cook the Shin Ramen noodles and included dried flakes packet for 4 minutes.
While the noodles are cooking, add the chopped onions and cabbage directly to the skillet with the chicken. Sauté briefly on medium heat until the vegetables are slightly softened and the chicken finishes cooking through.
Add the cooked and drained Shin Ramen noodles to the skillet with the chicken and vegetables.
Pour in the 2 tablespoons of chicken stock or water. Add the remaining half of the Shin Ramen seasoning packet. Toss everything together until the noodles are well coated in the spicy sauce and a cohesive sauce forms.
Transfer the flavorful ramen to a bowl. Top generously with sliced cucumber, crushed fried shallots, fresh chopped scallions, and crushed nori sheets. Serve immediately.