Very simple script I made that pops up an i3 message bar after a specific amount of time.
#!/bin/bash
TIME=$1
MESSAGE=$2
if [[ -z $1 ]]; then TIME=1s; fi
if [[ -z $2 ]]; then MESSAGE="Your timer is ready"; fi
sleep $TIME && exec i3-nagbar -t warning -m "$MESSAGE"
This allows me to set a timer when its too late to otherwise set it on my phone and no more will I burn pizza 
I can also be extra lazy and further automate it by setting an i3 hotkey for instant Pizza notification:
bindsym $mod+F10 exec ~/bin/timer 15m "Your Pizza is ready"