With one of the sticks of butter, grease bottom of cookie sheet(s) or pizza pans (including sides).
Combine remaining butter, corn syrup and water in a medium-size heavy saucepan. Cook over medium heat until butter is mostly melted. Stir in sugar and continue cooking over medium heat, stirring constantly, to 300o on a candy thermometer. (Do not rush the cooking, or the candy will be sticky. Constant stirring isn’t as critical up to 240 degrees, but becomes very critical at 240 and above.) As the temperature gets closer to 300o, slowly reduce stove temp to avoid burning. Once the temp reaches 300o, remove from heat; stir in vanilla, burnt sugar flavoring, and almonds (not including almonds for outside coating).
Spoon into the buttered pans, and using a pot holder covered in heavy-duty aluminum foil, quickly pound out the toffee to thin the candy evenly. Cool completely. Turn out onto wax paper.
Melt ½ of the chocolate in a microwave safe bowl at 50% power (stirring after each minute until it melted completely). Thinly spread the chocolate over the top of the candy; sprinkle with reserved almonds. Turn candy over. Melt remaining chocolate, spread over candy and top with remaining nuts. Let set until chocolate is firm (approximately 1 hour).
To speed the drying and hardening process, the candy can be put into the refrigerator until completely set. Break into pieces.