To make the burger patties, mix the ground beef and pork with the a good pinch of salt, pepper, chilli, fennel, paprika, garlic, oregano and balsamic vinegar until well combined. Form 6 patties around 2 – 3cm thick.
Mix the mozzarella with the basil leaves. Make an indentation in each patty and stuff some of the mozzarella mixture inside. Seal to enclose.
Heat a barbecue or frypan over medium -high heat. Add half the olive oil, capsicum and onion and cook, stirring every now and then for 20 minutes, or until very tender. Add the red wine vinegar and salt and toss to combine. Set aside.
Add a the rest of the olive oil to the pan/barbecue and cook the burger patties for 5 – 7 minutes per side, or until cooked through and cheese inside has melted. You can check by piercing with a toothpick. If the cheese is melted it will stick to the toothpick.
Meanwhile, cook the prosciutto for 2 minutes per side, or until crisp. Set aside and when cool enough to handle, crumble into small pieces. You can use kitchen scissors if you like.
Spread a little butter over buns and cook, cut side down, onto your pan/barbecue and lightly toasted.
To assemble, spread a little ricotta over the bottom half of each bun, top with a little spinach/rocket, then a burger patty. Sprinkle some prosciutto over, a little tomato sauce and then some capsicum/onion mixture. Top with the remaining bun halves and serve.
