Preheat oven to 110°C. Line 2 oven trays with baking paper.
Drizzle EVOO into a large saucepan over medium heat. Add 3 kernels popcorn. When they pop, add in remaining popcorn. Shake pan to spread corn out evenly. Cover with a lid.
When the popcorn starts popping in earnest, shake the pot gently constantly.
Remove from heat when the popping stops (when you can count to 3 between pops) and transfer to a bowl immediately to prevent burning. Set aside.
To make the caramel, melt butter in a saucepan over medium heat. Add sugar, golden syrup and salt. Stir until just combined.
When it starts to bubble, let it go for 4 minutes, Do NOT stir. Then take pan off the heat.
Quickly whisk in vanilla and baking soda until combined. Pour caramel over the popcorn and toss for approximately 2 minutes or until caramel cools and feels firmer.
Spread popcorn over 2 trays. Bake for 1 hour. Toss every 15 minutes.
Remove from oven and leave to cool. Break up into individual pieces if you wish. You could also salt the popcorn immediately after removing it from the oven if you wish.