When we originally featured this chicken dish, one of our paleo / Crossfit-ing members wrote me to say that this was the perfect post-workout meal. Whether you're pumping iron or not, this is a simple and healthy dish that'll help you refuel from a long day. Plus, you'll feel like a pro in the kitchen by making your very own pan sauce.
Place chopped sweet potatoes into a pot and cover with cold water by about an inch. Bring to a boil, and then simmer until you can easily insert a knife through the potatoes, ~6 to 10 minutes.
While sweet potatoes are cooking, heat a saute pan over medium-high heat. Add cooking oil, and then chicken to heated oil. Sear on both sides for 3 minutes.
Lower heat to medium, and add 2 more thyme sprigs, white wine, and chicken stock, scraping up any brown bits that may have formed on the pan. There will be some steaming action, so be careful! Cover and cook for another 4 to 6 minutes, until chicken has reached an internal temperature of 165F(74C) degrees. Instead of using a thermometer, I use touch. Press down on the chicken and if it has a little bit of give, it's done. Rock hard is overcooked, really squishable is still too uncooked.
Remove cooked chicken from pan and add mustard and corn starch mixture to the pan. Bring to a simmer and let sauce cook until it's thickened. Turn off heat, and add lemon, parsley, and season to taste with salt and pepper, and serve over chicken.
When sweet potatoes are done, drain and let steam for ~5 minutes so some of the moisture evaporates. Then mash with Greek yogurt, starting with less and adding more as needed. Season to taste with salt.