Set aside 50g each of the peanut butter
and chocolate. Heat oven to 180C/160C
fan/gas 4 and line a 20cm square baking
tin with baking parchment. Gently melt
remaining peanut butter, chocolate and
all the sugar in a pan, stirring occasionally,
until the sugar has just about melted.
Turn off heat and use a wooden spoon
to beat in the eggs one by one. Stir in the
flour and scrape into the tin.
Melt reserved peanut butter in the
microwave on High for 45 secs, or in
a pan, until runny, then drizzle over the
brownie. Bake for 30-35 mins until it
has a crust, but the middle still seems
Melt reserved chocolate, drizzle over
the brownie, then cool in the tin before
cutting into squares.