2 tablespoons canola oil
1/2 cup unpopped popcorn kernels
1/2 cup sliced almonds
2/3 cup packed brown sugar
2/3 cup light-colored corn syrup
2 1/2 tablespoons butter
1/2 teaspoon salt
1/2 cup creamy peanut butter
1 teaspoon vanilla extract
Preheat oven to 250°. Line a jelly-roll pan with parchment paper; coat paper with cooking spray.
Heat oil in a large Dutch oven over medium-high heat. Add popcorn; cover and cook 4 minutes, shaking pan frequently. When popping slows, remove pan from heat. Let stand until popping stops. Uncover and add almonds.
Combine sugar, syrup, butter, and salt in a medium saucepan and bring to a boil. Cook 3 minutes, stirring occasionally. Remove from heat. Add peanut butter and vanilla; stir until smooth. Drizzle over popcorn; toss well. Spread mixture out onto prepared pan. Bake at 250° for 1 hour, stirring every 15 minutes. Cool completely.