Preheat your oven to 400°F and line a small baking sheet with parchment paper.
Drain and rinse the chickpeas, pat them dry thoroughly with a paper towel, and toss with a tiny pinch of salt before roasting for 15-20 minutes until they reach a satisfying crunch.
Season the chicken breast with sea salt, black pepper, and a dash of garlic powder.
Heat a grill pan or outdoor grill over medium-high heat and cook the chicken for 6-7 minutes per side until the internal temperature reaches 165°F.
While the chicken rests, whisk together the olive oil, lemon juice, and Dijon mustard in a small bowl to create a light, emulsified dressing.
Place the mixed greens, halved cherry tomatoes, and sliced cucumbers in a large serving bowl.
Slice the grilled chicken into thin strips and arrange them over the bed of greens.
Sprinkle the warm roasted chickpeas over the top and drizzle with the lemon vinaigrette just before serving.