Spray bowl and utensils you will be using to mix popcorn in with a cooking oil to prevent sticking. Also, when the recipe says “do not stir for 4 minutes”...DON’T STIR!
Line 2 large sheet trays with waxed paper, set aside. Melt butter in a medium pot over medium heat. Stir in brown sugar, corn syrup, medium yellow curry powder, El Diente and salt. Bring to a rolling boil, stirring constantly. Continue to boil, and do not stir for 4 minutes; remove pot from heat and carefully stir in vanilla and baking soda until well combined.
Place popcorn in a large, oiled, bowl. Working quickly, pour hot caramel over popcorn and use a spoon to coat evenly. Transfer to reserved sheet trays and spread out in an even layer. Set aside to cool completely, then serve.
Store leftover popcorn in air tight containers or zip-topped bags.