I've also gotten more interested in cooking since I retired. I make dinner every Mon thru Fri, DW (still working) has made dinner twice in the past 18 months. My go to sources for online recipes are Ina Garten and Giada de Laurentis, and Marcela Valladoid for Mexican with a few from other FoodNetwork chefs.
As for something very simple yet tasty to do with chicken breasts, Chicken Vesuvio is one of our favorites. Here's a recipe similar to mine
Chicken Vesuvio Recipe : Giada De Laurentiis : Recipes : Food Network. I make it using chicken breasts, an everyday cast iron skillet and with frozen peas (instead of the artichoke/Lima beans). And any potato works, doesn't have to be red potatoes. A complete meal in 'one pot' - no sides needed. Yummy!
Other chicken "standards" at our house, Chicken Cacciatore, Curried Chicken, Coq au Vin, étouffée (+ shrimp & andouille), Jambalaya (+ shrimp), Chicken Mole Enchiladas, Chilaquiles, White Chili & Garlic Chicken w Fingerling Potatoes.
Where we used to make 2 serving dinners while we were both working, I usually make 6-10 servings now, and my freezer is well stocked. Why we never picked up on the ease of leftovers while working I can't explain. We eat much better, healthier and yet easier now. Too soon old, too late smart...