12 ounces chocolate (Katherine uses a combination of 4 ounces Baker's Unsweetened Chocolate squares and 8 ounces of Baker's Semisweet Chocolate squares)
1 cup coarsely chopped pecans *
Note: Katherine says the recipe will fail if margarine or unsalted butter is used, or if sliced almonds are substituted for slivered. Believe her.
* This is my personal note: Instead of chopped pecans, I sometimes like to use ground pecans as seen in the photo. Both work.
Instructions
Have a buttered baking sheet about 12-by-18-by-1/4-inch prepared and set aside before starting the toffee. In a medium saucepan, melt the butter over medium heat. Slowly add the sugar, stirring constantly until it dissolves. Do not stir in a circle. Instead, turn the mixture over as you stir to help the butter absorb the sugar.
Add the almonds. Stir in the same manner until mixture reaches the hard-crack stage (300 degrees F on a candy thermometer. The color should be dark amber and puffs of steam will emerge as it is stirred. (This could take from 35 to 45 minutes of constant stirring. The almonds will look a little burnt but that's what you want. Also, do not panic if before you reach the desired temperature the mixture seems to separate. Just keep stirring and eventually it will return to smoothness.)
In the meantime, place the chocolates in the top of a double boiler over gently simmering water and stir occasionally to melt. (I have this all ready to go and on the stovetop next to the toffee pan to make it easier to stir)
When the toffee is ready, pour it onto the prepared baking sheet and quickly spread it to even out the toffee. Allow it to rest for 5 minutes, then pour on the melted chocolate and spread evenly.
Sprinkle evenly with the chopped pecans on top of chocolate. Very gently press the nuts into the chocolate using the bottom of a glass. (I do this if using ground pecans too)
Allow toffee to harden without covering pan for 8 hours or overnight. Break toffee into pieces with your hands. Store in an airtight container in a cool place. Makes about 3 pounds.
Recipe by The Culinary Cellar at https://theculinarycellar.com/its-national-english-toffee-day/