Before I moved to New Zealand a cheese roll, to me, was a bread roll or bun filled with grated cheese and eaten as is. If you ask for a cheese roll here in New Zealand this is what you get:
If you don't want to get addicted to these then don't look at the recipe below. You have been warned!
1 pkt Maggi onion soup mix
1 can of carnation evaporated milk
1 cup cream
1 teaspoon mustard powder
500g grated cheddar cheese (medium to mild)
1 small onion very finely diced.
Put everything in a large microwaveable jug/bowl and heat for 6 minutes in 2 minute bursts, stirring in between. You will be left with a smooth gooey mass. Let it cool and it will firm up nicely.
The best bread to use is a soft white sandwich loaf, I have tried making them with every variety of bread and nothing comes close to the white sandwich loaf for taste and texture here.
Spread one side of the bread slices with the cheese mixture and fold into 3, I toast mine on a sandwich/panini press. They only take a few minutes, when they are nicely browned put them on a cooling rack and put another batch in to cook. You can eat them warm or reheat them later in the oven.
The recipe makes a lot, at least 2 full sized loaves-worth possibly 3. You can keep any unused cheese mixture in the fridge for a few days.