When cooking sugar to a high temperature, things move very quickly in the last few minutes or even seconds. To avoid burned sugar syrup, be sure to have the almonds toasted and ready to go before starting. A significant amount of vinegar in this brittle adds complex flavor.
1 1/4 cups slivered almonds, divided
2 1/4 cups sugar
1/2 cup whole milk
1/2 cup heavy cream
1/2 cup white vinegar
1/4 cup unsalted butter
1/2 teaspoon salt
How to Make It
Preheat oven to 350°.
Spread almonds in a single layer on a baking sheet. Bake at 350° for 10 minutes or until lightly browned and fragrant. Cool completely. Measure out 1/4 cup almonds; finely chop.
Cover a baking sheet with parchment paper. Lightly coat paper with cooking spray. Set aside.
Place sugar and remaining ingredients in a large saucepan over medium-high heat; bring to a boil, stirring constantly. Cook 20 minutes or until a candy thermometer registers 310°, stirring constantly. Stir in 1 cup almonds; cook an additional 1 minute, stirring constantly. Quickly pour mixture onto prepared parchment paper, spreading to about 1/8-inch thickness. Sprinkle chopped almonds over brittle, lightly pressing to adhere. Cool completely (about 2 hours); break into pieces.
Bake a Second Batch
Because the sugar syrup needs to be handled quickly, it's best not to double the amounts in this recipe. Instead, complete one batch before making the next.