Pat the chicken breast dry and season both sides with sea salt, black pepper, dried oregano, and fresh lemon zest.
Heat the extra virgin olive oil in a large skillet over medium-high heat until shimmering.
Add the chicken to the skillet and sear for 5 to 7 minutes per side, or until the internal temperature reaches 165 degrees Fahrenheit.
Remove the chicken from the pan and set it aside on a plate to rest, keeping the juices in the pan.
Lower the heat to medium and add the diced yellow onion to the same skillet, sautéing for 3 minutes until translucent.
Stir in the minced garlic and cook for 30 seconds until fragrant, then add the chopped collard greens.
Pour in the full-fat coconut milk and stir to combine, scraping up any browned bits from the bottom of the pan.
Simmer the greens for 5 to 8 minutes until they are tender and the sauce has thickened into a velvety consistency.
Stir the lemon juice into the greens and season with an extra pinch of salt if desired.
Slice the rested chicken breast and serve it immediately over the bed of creamy collard greens.