In a medium bowl, add chicken breast, minced garlic, and ¼ cup balsamic vinaigrette. Let sit for about 10-15 minutes.
In a large skillet, on medium heat, add 2 tbsp of oil and chicken breast. Cook for about 5-7 minutes on each side until chicken is thoroughly cooked throughout. Once chicken is cooked, removed from heat and cut into pieces.
In a large bowl, add pasta, chicken, diced tomatoes, basil, feta, and the rest of the balsamic vinaigrette. Toss until all ingredients are combined. Season with salt and pepper to taste.
To serve, spread the baby spinach (or arugula) on a large platter and scoop pasta on top. Sprinkle additional basil and feta on top, if desired.
Enjoy!