Any extra spices you might want to add
My Sophie used 500g of mince last night and it made 4 large burgers. She doesn't put them in burger buns which is why they are larger than the average burger. You can ofcourse use a smalled amount of mince or make smaller burgers to get more than 4.
Now, put about 6 crackers in a strong bag and roll with a rolling pin until they turn into fine crumbs. This is where you can replace the crackers with breadcrumbs.