Heat the Canola oil in a heavy-based pot on MEDIUM. Place 2 kernels in the pot. Cover with the lid and then listen for when the kernels pop.
Once the two kernels have popped, add the rest of the kernels in and shake to spread it evenly around the pot. Cover with the lid again and then listen to the popcorn pop until it is rapidly popping, then crack the lid slightly to let out a little steam.
Coat the popcorn in the melted butter, taco seasoning, and lime zest. Add in some salt if you like.