Recipe by Sam Linsell. A few notes on the recipe. Use any cheese you like with your cream cheese. I used a mature Cheddar and Parmesan combo, but choose whatever you prefer. I think a stronger cheese works well and adds depth of flavour to this dish. I used a liquid stock concentrate and added a bit extra as I wanted the meatiness (hence my description of 'concentrated' beef stock). If you use a cube, crumble in a bit extra. If you want your spinach layer to be more saucey, add 1/4 cup of cream or milk.