100g/3½oz gluten-free plain flour
280g/10oz caster sugar
50²µ/1¾´Ç³ú cocoa powder
125²µ/4½´Ç³ú milk chocolate (or more dark chocolate), broken into pieces
60²µ/2¼´Ç³ú milk chocolate chips
125²µ/4½´Ç³ú dark chocolate, broken into pieces
60²µ/2¼´Ç³ú dark chocolate chips
60²µ/2¼´Ç³ú white chocolate chips
250g/9oz unsalted butter, chopped into small pieces, plus extra to grease
4 free-range eggs