Preheat your grill or grill pan to medium-high heat and preheat your oven to 400°F.
Slice the zucchini into rounds and the red bell pepper into strips.
Toss the zucchini and bell pepper with 0.5 tsp of olive oil, sea salt, black pepper, and dried oregano.
Spread the vegetables on a baking sheet and roast for 15-20 minutes until tender and slightly browned.
Brush the chicken breast with 0.5 tsp of olive oil and season with a pinch of salt and pepper.
Grill the chicken for 5-7 minutes per side until the internal temperature reaches 165°F.
Let the chicken rest for 5 minutes before slicing into strips.
In a large bowl, whisk together the remaining 0.5 tsp of olive oil and the lemon juice to create a light dressing.
Add the mixed greens and roasted vegetables to the bowl and toss gently to coat.
Top the salad with the sliced grilled chicken and serve immediately.