Place the Aioli, chopped jalapeño peppers and brine in a jar and mix until smooth. Set aside until required.
Divide the mince into eight equal portions. Using clean hands, form each portion into plum-sized balls. Season with salt and spray a dot of oil on top each ball.
Heat 2 tablespoons of oil in large pan or hotplate. Add a ball of mince and using a metal BBQ flip, press the flip on top of the ball to press out into a very flat patty, you can drive the flip down further by pressing a wooden muddler onto the back of it. Repeat with the rest of the patties (you may have to cook in 2 batches). Cook for 2-3 minutes on high heat so you have a nice caramelised crust, then turn over and drape each patty with cheese. Cook until patties are starting to char and cheese is nicely melted.
In the meantime, warm brioche buns and slather bottom bun with the jalapeño aioli.
Stack two cheese patties onto each bottom bun and top with lettuce, tomato, onion, more jalapeño aioli and the top bun.
Serve with shoestring fries and extra jalapeño aioli for dipping.