Step 1 of 4

Melt the butter into the sugar and let it cool

Heat the oven to 350°F and line a 20 by 30cm pan. Melt the butter, stir it into the brown sugar until it looks like wet sand, and leave it for 5 minutes to come off the boil.

— Hot butter scrambles the eggs when they go in, and you will see it as little cooked flecks through the finished bake.