Grease a 15-inch baking sheet with a pad of butter and set aside.
Melt 2 cups of butter in a heavy saucepan over medium heat. Add the sugar, slivered almonds, water, and salt; cook and stir over medium heat until a candy thermometer reads 295°F (hard-crack is 300 degrees).
Remove from heat and stir in the Rodelle Vanilla Bean scraped seeds and the Rodelle Almond Extract. Quickly pour into the prepared pan.
Cool at room temperature for one hour.
In a microwave oven, or over a double broiler, melt the chocolate chips.
Add the Rodelle Vanilla Extract and stir until smooth. Spread 1/2 of the chocolate over the toffee in a thin layer.
Refrigerate for about 45 minutes until cool.
Invert the toffee onto another sheet and spread the remaining chocolate over the toffee (you may need to briefly reheat the chocolate).
Sprinkle the chopped almonds in an even layer over the top, press down gently to set almonds into the chocolate.
Let stand for one hour. Break into bite-sized pieces. Store in an airtight container.
