Make the Chicken Marinade: In a large bowl, whisk together the olive oil, lemon juice, garlic, oregano, paprika, salt, and black pepper. This marinade will infuse the chicken with Mediterranean flavors, ensuring each bite is aromatic and delicious.

Marinate the Chicken: Add the chicken thighs and turn until completely coated. Cover and refrigerate for 30 minutes. Avoid marinating for several hours because prolonged exposure to lemon juice can gradually change the chicken’s surface texture, making it less enjoyable.

Prepare the Tzatziki: Squeeze the grated cucumber firmly in a clean kitchen towel or fine-mesh strainer to remove excess moisture. Stir it together with the Greek yogurt, lemon juice, olive oil, dill, grated garlic, and salt. Refrigerate until serving to allow the flavors to meld.

Make the Cucumber-Tomato Topping: In a medium bowl, combine the tomatoes, diced cucumber, red onion, parsley, lemon juice, olive oil, and salt. Toss gently and set aside while the chicken cooks, allowing the flavors to combine and the vegetables to soften slightly.

Preheat the Grill: Preheat an outdoor grill or grill pan to medium-high heat, approximately 400°F to 450°F (205°C to 230°C). Clean and lightly oil the grill grates if necessary to prevent sticking and ensure even cooking.

Prepare the Chicken for Grilling: Remove the chicken from the marinade and let heavy excess marinade drip back into the bowl. Discard the marinade that contacted the raw chicken to avoid contamination.

Grill the First Side: Place the chicken thighs on the hot grill in a single layer. Grill without moving them excessively for 5 to 6 minutes, until they release easily and have dark golden grill marks, which indicates a good sear.

Turn and Finish Cooking: Flip the chicken and grill for another 4 to 6 minutes. The thickest portion must reach 165°F (74°C) to ensure it is fully cooked and safe to eat.

Rest the Chicken: Transfer the cooked chicken to a clean cutting board and let it rest for 5 minutes. This helps the juices settle before slicing, ensuring each piece remains moist and flavorful.

Warm the Tortillas: While the chicken rests, place the tortillas on the grill for about 20 to 30 seconds per side, just until warm, flexible, and lightly marked. Stack them under a clean kitchen towel to keep them soft and pliable.

Slice the Chicken: Cut the rested chicken across the grain into thin strips or bite-size pieces. The interior should be opaque and juicy with no translucent areas, indicating it is cooked through.

Drain the Vegetable Topping if Needed: If the cucumber-tomato mixture has released significant liquid, spoon off the excess before assembling the tacos so the tortillas do not become soggy, maintaining the desired texture.

Assemble the Tacos: Spread or spoon tzatziki onto each warm tortilla. Divide the grilled chicken among the 8 tortillas, then top with the cucumber-tomato mixture for a fresh crunch.

Add the Feta: Sprinkle the 3/4 cup (90 g) crumbled feta evenly over the tacos. This adds a salty, tangy flavor that complements the chicken and vegetables beautifully.

Garnish and Serve: Finish with optional fresh herbs, crushed red pepper flakes, or a squeeze of lemon. Serve immediately while the chicken and tortillas are warm for the best experience.