Season the chicken breast evenly with sea salt, black pepper, and dried oregano.
Heat the olive oil in a medium skillet over medium-high heat.
Place the chicken in the skillet and sear for 5-6 minutes per side until golden brown and cooked through.
Remove the chicken from the pan and set it aside on a plate to rest.
Lower the heat to medium and add the minced garlic to the same pan, sautéing for 30 seconds until fragrant.
Pour in the full-fat coconut milk and lemon juice, scraping up any browned bits from the bottom of the pan.
Add the baby spinach to the sauce and stir until it is just wilted.
Return the chicken to the pan, spooning the creamy sauce over the top to coat.
Serve the chicken and creamy sauce immediately over the warm, cooked brown rice.