In a mixing bowl, whisk together the Greek yogurt, mayonnaise, minced shallot, chopped parsley, cilantro, extra virgin olive oil, red wine vinegar, and a pinch of kosher salt. Blend until smooth, then set aside.

In a small bowl, combine garlic powder, kosher salt, and black pepper. Generously season the chicken breasts on both sides. Let sit for about 10 minutes.

Heat a skillet over medium heat and drizzle olive oil. Add the seasoned chicken and cook for 6–7 minutes per side until golden brown and cooked through. Remove from pan and let rest before shredding.

In the same skillet, add a splash of olive oil and sauté sliced jalapeños and red onions for 3–4 minutes until softened.

Return the shredded chicken to the skillet and stir with jalapeños and onions. Toss in chopped cilantro and remove from heat.

Warm the tortillas, then layer each with lettuce, a serving of the chicken mixture, avocado slices, chimichurri sauce, and sprinkle with feta cheese.