Cook the dry white rice in water according to package directions until fluffy.
Season the chicken breast evenly on both sides with sea salt, black pepper, garlic powder, and dried oregano.
Heat a high-quality non-stick skillet over medium-high heat and add 2 tablespoons of the chicken broth to the pan.
Place the chicken in the skillet and sear for 6 to 8 minutes per side until cooked through, adding a splash more broth if the pan becomes too dry.
Remove the chicken from the skillet and let it rest on a cutting board for 5 minutes.
In the same skillet, add the remaining chicken broth and lemon juice, stirring to scrape up any flavorful browned bits.
Add the fresh baby spinach to the skillet and sauté for 1 minute until just wilted.
Fold the wilted spinach and the lemon-broth liquid into the cooked rice until well combined.
Slice the rested chicken breast into strips and serve immediately over the spinach rice.