Combine the sugar, butter, brown sugar, glucose syrup, sweetened condensed milk, and salt in a heavy saucepan. Cook to 150°C/302°F while stirring constantly.
Remove from the heat and stir in the vanilla extract.
Pour the mixture into a frame 16 × 24 × ¼ in set on oiled parchment paper.
Press the toasted Brazil nuts into the toffee and allow