I just cook stuff that basically cooks itself. Crockpots, pasta, certain veggies and meats on the oven. After doing them many times I already know the timings for everything so I just put alarms to remind me of turning the fire off/flipping them in the oven once and that's it. Doing something else in between. Technically speaking you spend only a couple minutes actively cooking for each meal that way. Just don't forget to set the alarms or it's burnt (and move the particular meat from the freezer to the fridge the night before)