Prepare a baking sheet lined with parchment paper or a silicone mat.
Pop the kernels using your preferred method (microwave, stovetop or machine). Spread them out on the baking sheet, making sure to remove any unpopped kernels, and place in the oven. Then turn your oven on to 90°C/195°F.
In a large pot, combine the brown sugar, maple syrup, coconut oil, milk and salt and place over medium heat.
Bring to a full boil (not just the edges) gently stirring occasionally with a silicone spatula to avoid it catching.
Once it’s boiling, turn off the heat but leave it on the burner. Take out the sheet of popcorn from the oven, raise the temperature to 150°C/300°F and keep the sheet near the stovetop.
Stir the vanilla into the caramel then stir in the baking soda. It will foam up and lighten, that’s normal.
Add the popcorn and gently stir until everything is fully coated.
Spread out onto the baking sheet and bake for 10-15 minutes (or more if you want it darker) stirring once halfway through.
Let the popcorn cool completely on the tray before eating or storing in an airtight container.