Spray a 9 1/2‐by‐12 1/2‐inch rimmed baking sheet (also called quarter‐sheet pan) with cooking spray. Line with parchment; spray parchment.Advertisement
In a saucepan, combine sugar, corn syrup, and 1 cup water. Bring to a boil, stirring, just until sugar has dissolved, then cook until syrup reaches 250°F (firm ball stage) on a candy thermometer.
Meanwhile, in the bowl of a mixer fitted with the whisk attachment, starting on low speed and gradually increasing to high, beat egg whites with salt until stiff peaks form. If peaks form before syrup reaches 250°F, reduce speed and keep mixer running on low.
Reduce speed to medium and add syrup in a slow, steady stream (taking care not to hit whisk or side of bowl). Add vanilla. Increase speed to high and continue to beat until mixture is very thick and begins to lose its gloss, 10 to 20 minutes. Fold in pecans and candied fruit. Scrape mixture into prepared pan, using hands sprayed with cooking spray to press in evenly.
Let stand until fully set and dry on top, at least 8 hours. Transfer to a cutting board; cut into 3/4‐by‐3‐inch pieces. Store in a single layer on parchment‐lined baking sheets, wrapped in plastic, at room temperature up to 1 week.
To get neat slices of nougat, use a clean, warm knife; dip it in hot water and wipe dry between cuts.