Cook the whole wheat penne pasta in a large pot of boiling salted water until al dente, then measure out 0.75 cup and set aside.
Season the chicken breast on both sides with sea salt, black pepper, and dried oregano.
Heat the extra virgin olive oil in a large skillet over medium-high heat.
Add the chicken breast to the skillet and sear for 5-7 minutes per side until golden brown and cooked through.
Remove the chicken from the pan, let it rest for a few minutes, then slice into thin strips.
In the same skillet, add the minced garlic and sauté for 30 seconds until fragrant.
Stir in the fresh lemon juice and lemon zest, scraping up any flavorful browned bits from the bottom of the pan.
Add the baby spinach to the skillet and toss for 1 minute until just wilted.
Add the cooked pasta and sliced chicken back into the skillet, tossing everything together to coat in the lemon sauce.
Garnish with fresh parsley and grated parmesan cheese before serving warm.