Aubergine parmigiana sandwich

Method

1. First, make the red sauce. Put the oil in a pan over a medium heat with the onion, garlic and chilli and cook for 10-12 minutes until soft and beginning to caramelise. Season with salt, then add the tinned tomatoes, herbs, vinegar, sugar and some black pepper. Bring to the boil, then simmer until the liquid has reduced by a third (15-20 minutes). Remove the bay leaves, then use a stick blender to whizz until fairly smooth. Check the seasoning and adjust if necessary.
2. Meanwhile, start the parmigiana. In a large bowl, toss the aubergine slices with the salt, some pepper and a splash of olive oil, then set aside in a colander for 20 minutes – there’s no need to soak or rinse.
3. Heat the oven to 200°C/180°C fan/gas 6. Spread a spoonful of red sauce in the baking dish, then add a layer of aubergine. Sprinkle with a handful of parmesan and some basil, then repeat the layers until all the aubergine is used. Finish with red sauce, a layer of mozzarella followed by more basil leaves, and finally add the breadcrumbs and remaining parmesan. Grind over some black pepper, cover with foil, then bake for 20 minutes.
4. Remove the foil after 20 minutes and return to the oven for 30-35 minutes until the aubergines are soft and the cheese is golden. Set aside to cool completely – ideally overnight to allow the flavours to develop (see Make Ahead).
5. To make the chilli mayo, whizz the egg yolks, mustard, vinegar and salt in a food processor or mini blender, then trickle in the oil so it emulsifies – add a little hot water if it starts to get too thick. Add the fermented chilli paste, check the seasoning and set aside. (If you don’t have a processor/blender, use the stick blender and a bowl or jug).
6. To assemble and serve the sandwiches, heat the oven to 200°C/180°C fan/gas 6. Cut the parmigiana into rectangles the same size as the bread and put on an oven tray to warm through (see Make Ahead). Heat a griddle pan, then toast the cut sides of the focaccia. Drizzle olive oil over the focaccia pieces that will form the base of the sandwiches, then spread the tops with fermented chilli mayo.
7. Put a slice of hot parmigiana on the bottom piece of bread, tear the burrata over the top, then season with salt and pepper. Toss the rocket and basil with a little oil and sherry vinegar, then pile onto the burrata. Finish with a sprinkling of parmesan, then sandwich together and serve straightaway.