Place 1 tablespoon coconut oil into a deep pot or pan with a tight-fitting lid and melt over medium-high heat. Add in popcorn kernels and cover. Shake the pan back and forth every 20 seconds or so to heat kernels evenly. After about 2 minutes, kernels should start to pop. Once popping slows, remove popcorn from heat and pour into a large bowl.
In a small saucepan, place remaining coconut oil with maple syrup and salt. Boil 2 minutes, then remove from heat and stir in vanilla. Drizzle over popcorn and toss to coat evenly. Spread out onto some parchment paper to cool 30 minutes or so. Serve.