When the spinach comes to the boil, stir in the instant mashed potatoes (don't add water, the liquid in the spinach will soak it up, making the swampthing this heavy). It will usually take around 5 minutes for a packet to be completely incorporated. You can adjust the thickness by adding more instant mashed potatoes or by adding milk.

Combine the spinach mixture with the beef and cheese (optionally save some cheese to put on afterwards). Taste and adjust final seasoning.

A serving consists of around one large ladle.