I started this meal with this recipe for caramelized onion, apple and blue cheese panini, and immediately made some changes to it because we don't have any apples and my boyfriend doesn't like blue cheese.
I fried two thin pork steaks (escalopes?) in oil on a high heat for two minutes, and then on a medium-high heat for a further five, flipping once. Flipped them again at the end to get some colour on each side. Sliced two smallish onions. Removed pork from pan, added onions along with a little bit of vinegar to deglaze. Once the onions were soft, I added a few splashes of balsamic vinegar and a teaspoon of sugar. Turned heat down to low.
Placed pork on toast. Cut to fit (eating a few bits along the way). Dolloped lots of caramelized onions on top, with a couple of handfuls of grated mozzarella and six to seven teaspoon-carved bits of blue cheese on top of that, and the other slice of toast on the very top. Put sandwich in a non-preheated oven at 180 degrees C for about five minutes till the cheese went melty. Then had to add more caramelized onions as there were tons left over.
Tom put some pork on each slice of toast, covered each with half a slice of cheese (Emmentaaler, I believe) and put them in the oven for five minutes. Removed, added a handful of mozzarella to each, replaced in oven for another five minutes. Removed, caramelized onions added, the whole thing squashed together and eaten.
It was a brilliant messy lunchtime, with one pan used for all the cooking. Tom insisted that the sandwich would have been improved with the addition of mayonnaise, but that opinion is to be rejected as he is obsessed with mayonnaise and thinks that everything would be better with it. I foresee home-made mayonnaise in my future...