Toad in the Hole with caramelised onion gravy

I was having a chat with one of my bosses at work last week and he was telling me about the disaster that was his toad in the hole. He listed the many problems and issues he had with it: his friends kept opening the oven door, the roasting tin wasn't big enough and there were too many sausages. 
This led me to crave toad in the hole and so I decided to make my own. 
For a dish big enough for three people you'll need:
100g plain flour
300ml milk
2 eggs
salt and pepper
half a teaspoon of dried mixed herbs
2 large pork sausages (or three skinny chipolatas) per person
sunflower oil (around 4 tablespoons- enough to coat the bottom of the roasting tin)
A large, deep roasting tin (Mine was 30cm by 20cm)

For the caramelised onion gravy:
2 red onions, halved and finely sliced
1/2 tsp coarse salt
1 tsp of butter
1 tbs sunflower oil
2 tsp soft brown sugar
1 tbs balsamic vinigar
1 tbs gravy granules for meat (not chicken).
Half a pint just bolied water

Pre-heat the oven to 200oC
Put the sausages and oil into the roasting tin and put into the oven for ten minutes.
Meanwhile, to make the batter, put all the remaining ingredients into a bowl and whisk until well combined and a light froth has formed on the top.

When the sausages have gone very lightly brown, pour in the batter around the sausages and quickly shut the oven door. As soon as the oven loses its temperature the batter will lose its rise, much like a souffle. Leave to bake for fifteen minutes.

And now to gravy which, luckily enough takes around fifteen minutes to make.
In a frying pan, melt the butter in the oil and add in the sliced onions and salt (the salt stops the onions browning and draws out their moisture). Using a wooden spoon, separate the rings on the onions so you have a pan full on thin onion tendrils. Leave the onions on a low heat for fifteen minutes to soften.
Check the toad is ready and turn the oven off and put your plates in there to warm up.
Add the brown sugar to the onions and let it bubble before adding the balsamic vinegar. 
Let the vinegar cook into the onions before adding the gravy granules and boiling water to make a gravy of your preferred thickness.

Take the plates out of the oven along with the toad. 

Serve it up with lashngs of gravy and sides of your choice - I went for veg but I also love a good mound of mashed potato or even roasties.