In a large Dutch oven or thin-bottomed pot with a lid, heat oil over medium heat. Add a couple kernels of popcorn and wait for them to pop to ensure the oil is hot enough.
When the test kernels have popped, add in popcorn kernels and sprinkle in white & brown sugar. Cover and continually shake pot back and forth on burner while the popcorn pops until there is a 3 second gap between any popping.
Immediately pour popcorn into a large bowl. Sprinkle evenly with salt and toss well to coat.
Allow popcorn to cool completely before storing in an airtight bag. Break apart any chunks that are stuck together. Popcorn will stay fresh for at least 2 weeks.
