Season the chicken breast evenly with half of the sea salt, black pepper, and dried oregano.
Preheat a grill or grill pan over medium-high heat and lightly coat with a small amount of oil to prevent sticking.
Grill the chicken for 6 to 7 minutes per side, or until the internal temperature reaches 165°F and the exterior is golden brown.
Remove the chicken from the heat and let it rest for 5 minutes before slicing into thin strips.
In a small jar or bowl, whisk together the extra virgin olive oil, balsamic vinegar, and the remaining salt, pepper, and oregano to create the dressing.
In a large serving bowl, combine the mixed baby greens, blueberries, and sliced strawberries.
Drizzle the dressing over the salad and toss gently to coat the leaves.
Top the salad with the sliced grilled chicken, crumbled feta cheese, and sliced almonds for a final layer of texture.