1 Line a 9- by 9- by 2-inch baking pan with foil, extending foil over edges of pan. Spray well with cooking spray.2 Spread almonds in bottom. Place sugar in a medium pot with lemon juice and 1/4 cup water.3 Stir and turn heat to high. Monitoring carefully, let color come to light brown, mixture will bubble. Add butter, cream and corn syrup, and stir.4 Clip a candy thermometer to the side of pot. Reduce heat to medium and let mixture come to a gentle boil. 5 Stirring frequently, continue to boil until mixture reaches 248°F (firm-ball stage) on candy thermometer; this may take up to 45 minutes. 6 Meanwhile, cut vanilla beans in half lengthwise and scrape out seeds; reserve, discarding pods. Remove caramel from heat and stir in vanilla. 7 Quickly pour into prepared pan, pouring evenly over almonds. Let cool for about 10 minutes, then sprinkle evenly with sea salt. Let cool completely, and pull out foil from pan. 8 Remove foil and cut caramels into 1- by 1-inch squares. 9 Serve, or wrap each one in plastic wrap or food-safe cellophane. 10 Seal with tape or a little sticker, if desired, and store for up to 2 weeks.