Dice the chicken breast into bite-sized pieces and season with sea salt, black pepper, and dried oregano.
Heat the olive oil in a large non-stick skillet over medium-high heat.
Add the chicken to the skillet and sear until golden brown on all sides, then remove the chicken and set aside.
In the same skillet, add the minced garlic and jasmine rice, stirring for 1 minute to lightly toast the grains.
Pour in the chicken broth, lemon juice, and lemon zest, scraping the bottom of the pan to release any browned bits.
Return the chicken to the skillet and bring the liquid to a gentle boil.
Reduce the heat to low, cover with a tight-fitting lid, and simmer for 15 minutes or until the rice is tender and the liquid is absorbed.
Remove from heat, place the baby spinach on top, and cover for 2 minutes to let the steam wilt the greens.
Stir the spinach into the rice and serve immediately.