Season the Breasts: Pat the chicken breasts dry with paper towels, then brush both sides lightly with 1 tablespoon of olive oil. In a small bowl, combine the paprika, garlic powder, black pepper, and salt, then sprinkle the seasoning mixture evenly over both sides of the chicken.
Preheat the Grill: Heat your grill to medium-high heat (about 375-400°F) for 5 minutes, or heat a grill pan over medium-high heat on your stovetop.
Grill the Chicken: Place the chicken breasts on the grill and cook for 6-7 minutes on the first side without moving them, allowing nice grill marks to form. Flip and cook for another 6-7 minutes on the second side until the internal temperature reaches 165°F (74°C) when measured with a meat thermometer at the thickest part.
Rest and Slice: Transfer the chicken to a cutting board and let it rest for 3-5 minutes before slicing into bite-sized pieces or strips.
Prepare the Vegetables: Chop the romaine lettuce into bite-sized pieces and place in a large salad bowl. Slice the hard-boiled eggs and set aside. Slice the cucumber into thin rounds or half-moons. Cut the cherry tomatoes in half.
Make the Dressing: In a small jar or bowl, whisk together the 3 tablespoons of olive oil, 1 tablespoon of lemon juice, and 1 teaspoon of Dijon mustard.
Season the Dressing: Add a pinch of salt and pepper, then whisk vigorously for about 30 seconds until the dressing becomes slightly thicker and emulsified.
Build the Base: Start with your chopped romaine lettuce in a large bowl or on individual plates.
Layer the Vegetables: Arrange the cucumber slices, cherry tomato halves, and hard-boiled egg slices over the lettuce.
Add the Chicken: Top with the warm or cooled grilled chicken strips, distributing them evenly across the salad.
Dress and Serve: Drizzle the lemon dressing over the salad just before serving, or serve the dressing on the side so each person can dress their salad to taste.