Let cool for five minutes then mix in flour, sugar, eggs and salt, beating well after each ingredient.
Butter and flour a 9 inch cake pan (Max uses a fluted edged pan for a pretty effect) and pour in batter.
Bake at 375° F for about 20 minutes. Just the edges of the cake should be cooked through - the center should still be a bit soft. Let cool.
This tastes great if you serve it while it is still warm.