Why are my outlets dead after replacing a light switch?
That &quot;extra&quot; wire was bundled with the incoming hot, so put it back with the incoming hot
As it turns out, that &quot;extra&quot; wire wasn't so extraneous after all as it was feeding power to the dining room light and kitchen outlet in question.  In order to get things back working again, you'll want to nut said &quot;extra&quot; wire in with the incoming always-hot to the box and a pigtail of wire going off to one brass screw on the light switch.  The remaining black wire, then, is the switched-hot going off to the laundry room light, and thus needs to land on the other brass screw on the light switch.