Preheat your oven to 400°F (200°C) and line a baking sheet with parchment paper.
Peel and cube the pumpkin into bite-sized pieces, then toss with half of the olive oil and a pinch of salt.
Roast the pumpkin for 15-20 minutes until tender and slightly caramelized.
Season the chicken breast with salt and pepper, then grill over medium-high heat for 6-7 minutes per side until fully cooked.
Steam the broccoli florets for 3-4 minutes until they are vibrant green and slightly crisp.
Hard-boil the egg, remove the shell and the yolk, and finely chop the egg white.
In a small jar, whisk together the remaining olive oil and lemon juice to create a light vinaigrette.
In a large salad bowl, combine the mixed greens, cherry tomatoes, roasted pumpkin, and steamed broccoli.
Slice the grilled chicken breast into thin strips.
Top the salad with the sliced chicken and chopped egg whites, then drizzle with the lemon vinaigrette and serve.