Pat the chicken breast dry with paper towels to ensure a golden crust, then season both sides evenly with chili powder, sea salt, and black pepper.
Heat the olive oil in a cast-iron or stainless steel skillet over medium-high heat until shimmering.
Place the chicken in the skillet and sear for 5 to 6 minutes per side until the internal temperature reaches 165°F and the exterior is beautifully browned.
While the chicken rests, add the corn kernels to the same skillet and cook for 3 to 4 minutes, stirring occasionally until they are toasted and charred.
Slice the rested chicken into thin strips against the grain for maximum tenderness.
In a small bowl, toss the shredded cabbage with lime juice and chopped cilantro to create a bright, acidic slaw.
Briefly warm the corn tortillas in a dry pan or over an open flame, then assemble the tacos by layering the chicken, charred corn, cabbage slaw, and fresh avocado slices.