Never mind whats in ones sarnie. Lets look for a moment at who made it.
Or more to the point which gender does said sarnie maker belong to.
Wimmin cannot make proper sarnies. All blokes know this.
Wimmin sarnies consist of summat (usually with a high rabbit food content) in the middle of a slice of bread with acres of space between that and the crust.
Bloke sarnies consist of mahooshive filling with a bit of bread on the bottom and (if your not posh or Norgwegian) on the top as well.
It's the same for cobs (insert generic local term such as barm, batch etc here) if a bint makes it you need an MRI scanner to find the filling.
I make my own packed lunch and Mrs TG is quite happy for me to make hers as well funnily enough.