Toast the almonds in a pan over a low heat or in an oven on a baking sheet in medium heat. Stir frequently to avoid the almonds burning. Afterwards, chop the almonds into medium-size pieces. I usually put them in a ziplock bag and roll a rolling pin over it until the pieces look a good size. Put them aside until needed.

Measure the chocolate and chopped pecans before starting to cook the caramel mixture on the stove, as you will need to add these quickly and might not have time later to prepare them.

Put the sugar, butter, salt, and vanilla extract in a heavy saucepan over medium-high heat. The saucepan should be large enough for the ingredients to boil up towards the top without overflowing.

Stir gently and continue over medium-high heat until the mixture starts to boil.

Reduce the heat to medium or medium-low and continue to cook about 12 minutes. (Note the time may vary if you make a smaller or larger quantity of English toffee.) Stir gently but not constantly while it boils until it reaches the "hard crack stage", which is at 300F (150C) if you use a candy thermometer. Otherwise, you will need to determine when it's done by observation and testing. (See notes). When it reaches the hard crack stage, turn off the heat and remove the saucepan.

Line a 7 x 11 inch (18 cm x 28 cm) shallow pan with baking paper. Spread the toasted chopped almonds on the surface.

Stir the boiling mixture one more time. Do this only if it's immediately after removing the boiling mixture from the stovetop. If it's minutes later, skip it, or else the sugar can start to crystalize. Pour the caramel mixture over the chopped almonds. Using a wooden spoon or silicone spatula spread out the caramel evenly over the almonds.

Distribute the chocolate chips or chocolate bar all over the top of the hot caramel-almond mixture. Using a knife or spatula, spread the chocolate as it melts over the top. Then sprinkle the chopped pecans on top of the chocolate.

Let the English toffee cool off completely. I usually put it in the refrigerator for at least an hour to speed up the cooling process. If I make it at night, I'll leave it in the refrigerator overnight. Once it's cool, take a sharp knife and cut the English toffee into pieces. If you don't care if the pieces are uniform, you can merely break the English toffee into different-sized pieces.

You can leave the English toffee in the refrigerator for a long time. Believe me, it will not last long enough to test how long it can last there. Otherwise, you can wrap the pieces in baking paper or thin foil and put them in a tin or plastic container. Serve and enjoy!