...and add the time for preparation, cleaning up etc.: Thats one of the most frustrating things when cooking for one person - you invest 45min to eat 5min and the rest is "organisation & logistics"
so: - 5 min walk to supermarket - 10 min in there - 5 min walk back home - washing & cutting wedgetables 7 - 10 min - maybe cutting some meat: 5 min on top - eating 5 - 10 min - cleaning up the kitchen 5 min
I don't count the walk to the supermarket since even if you eat out almost every meal, you still tend to need to go to the grocery for items either way. And if you eat out, you still have to go there and back.
Cutting should be in parallel with cooking. Similar to cutting, cleaning should also be in parallel with cooking. For example, my knife and cutting board are washed, dried and put away before my sauce finishes simmering down.