Bring milk and sugar to almost boiling point, remove from heat, stir in the water to lower temp. Whisk in the sugar, yeast and melted butter, allowing the yeast to froth for 20 minutes. Mix flour and salt and knead into a soft dough with the yeasted liquid, cover, allow proving for 1 hour. Turn out the dough onto a lightly dusted surface and roll into 1.5cm thickness. Cut with a 5cm cutter. Cover and allow resting for further 20 minutes until doubled in bulk. Lightly grease a griddle pan and cook on moderate heat for approx. 10 minutes on each side. Set a small pot of simmering water, stir in the vinegar and salt to taste. Poach the eggs carefully in the simmering water. In a separate pan, melt a spoon full of butter, add in the spinach, salt, pepper and nutmeg, and cook till spinach is wilted. For the Béchamel, mix the melted butter and flour in a thick bottom sauce pan, pour the milk gradually, stirring continuously to avoid lumps and from burning in the bottom, season the sauce with salt, pepper and cheese. To serve, serve warm muffins, topped with the spinach, poached egg and the parmesan béchamel.