Season the chicken breast evenly with ground cumin, smoked paprika, garlic powder, sea salt, and black pepper.
Poach or steam the chicken breast until it reaches an internal temperature of 165 degrees Fahrenheit and is tender enough to shred.
Use two forks to shred the cooked chicken into bite-sized pieces.
Heat the extra virgin olive oil in a cast-iron skillet over medium-high heat until shimmering.
Add the shredded chicken to the skillet and press down with a spatula, searing for 3-4 minutes until the edges become golden and crispy.
Warm the corn tortillas in a separate dry pan over medium heat until they are soft and pliable.
Finely dice the red onion, roughly chop the fresh cilantro, and thinly slice the radishes.
Divide the crispy shredded chicken between the two warm tortillas.
Garnish the tacos with the red onion, cilantro, and radishes, then serve immediately with a fresh squeeze of lime juice.