Lightly butter a 13 x 9-inch baking dish. Set aside.
Measure the crushed fritos and place in a large mixing bowl. Set aside.
In a medium saucepan, over medium heat, combine the sugar and white corn syrup. Stir to form a sandy paste. Bring the mixture to a boil, stirring often. The sugar will dissolve and the mixture will become clear. Once the mixture is at a full rolling boil, bubbles that cover the surface, remove from the heat.
While the syrup mixture is still very hot, stir in the peanut butter. Stir until mixture forms a thick glossy sauce.
Pour mixture over crushed fritos in large bowl. Stir gently until fritos are completely coated. Pour the frito mixture into the buttered dish. With the back of a buttered spoon or using your buttered hands, firmly and evenly press mixture into prepared dish.
In a small bowl, combine the chips. Melt the chips in the microwave on high for 30 seconds, then stir. Repeat until just a few tiny pieces remain. Stir until the last pieces remain.
Pour the melted chips over the frito mixture, scraping the bowl with a rubber spatula. Smooth melted chips into an even layer with the back of an off-set spatula.
Let the bars 'set up' for a few hours before serving. Cut into bars.