Oven to 170°C. Toast the pecan nuts for a few minutes on a baking tray in the oven, and then chop up roughly.
Grease a 28cm x 23 cm x 4cm grease-proof cake tin or roasting tin and line the bottom with baking paper.
Mix the cream cheese, caster sugar, 1 tbsp of plain flour and egg yolk together with a whisk and then cover with cling film and chill.
Mix the nuts with the 200 g plain flour.
Your 5 eggs should measure about 300 ml. Whisk the egg yolks and sugar with an electric beater, until pale and thick which should take at least 5 minutes.
Melt the 200g chocolate over a bowl of barely simmering water and then add in knobs of butter. Mix well. Fold the chocolate mix into the beaten eggs and then quickly fold in the flour & nuts. Pour into the tin, and then using two teaspoons, drop knobs of the cream cheese mix in rows.
Once you have done that, you can pat them down, so that they sink.. Ideally, you could do this with a piping bag, but piping bags are a pain to use for such a small job, so I don’t bother. Bake for at least 40 minutes. They look a bit pale rather than dark chocolate colour, but once a skewer is reasonably clean, remove from the oven and allow to cool.
Make the glaze by bringing the butter and water just to the boil, then pouring on top of the chocolate. Stir gently, slowly incorporating the liquid into the centre and it should form a nice sheen.
Once cool enough to spread, ice the brownies, then slice and serve.