At this point, the potatoes and broccoli should be now out of the oven cooling. I did eat my salad when it was still a little warm and it was delicious. But you can wait for everything to cool down if you want more of a traditional cooled potato salad. I ended up having it cooled the next day after storing it in the fridge and it was amazing that way too.
Chop the onion very finely and add to a big salad bowl. Add the cooled potatoes and broccoli to the bowl as well as the candied pecans.
Begin by adding a little bit of the dressing at a time and tossing the salad. I didn't end up using all of the dressing I made (although I did use most of it) so I will leave that up to you for personal preference. But I would suggest adding a little at a time to start off with.
Store the salad in an airtight container in the fridge for a few days. The dressing can remain in the fridge as well if you have any remaining.