In a large skillet, heat 1 tablespoon of oil over medium-high heat. Place the chicken breasts (round side down) in pan and sprinkle with ½ a teaspoon of oregano, ¼ teaspoon salt, and the black pepper. Cook for 4-5 minutes. Flip, reduce the heat to medium, and cook for 5-7 minutes more, until cooked through.*
Remove chicken and set aside. In the same pan, heat remaining oil. Brown the onion rings for 2 minutes over medium-low flame.
Add the remaining ingredients to the skillet, stirring to dissolve the arrowroot starch. Let cook, continuing to stir occasionally, for 15-20 minutes, until sauce gets slightly thicker.**
Return the chicken to the pan and baste with the sauce. Serve hot.
Store in airtight container in the fridge for up to 1 week.
Notes
*This depends on how thick your chicken breasts are. Mine needed about 7 minutes more. **The sauce does not reduce to a very thick gravy-like texture, but you'll notice that it's less liquid than when you started. It should reach a light boil at least before you add the chicken back to the pan.
Recipe by Lenses and Lentils at https://lensesandlentils.com/one-skillet-white-wine-chicken/