For the mayo, mix the garlic and paprika in a bowl. Stir in the mayo.
For the burgers, heat the olive oil in a pan. Gently cook onion and garlic until soft, but not coloured. Leave to cool.
In a large bowl mix the raw beef, cooked onion, cayenne, salt, pepper and ketchup. Work in the egg yolk. Add breadcrumbs and fold in parsley.
Using your hands (oiled to prevent sticking), form 5 patties, 2-3cm thick. Lightly oil the burgers and refrigerate until required.
Have the barbecue coals ready – not too hot. Brown the burgers on the first side for 4-5 mins. Repeat on the other side. Turn 90° to get the cross-hatched effect. You can use a griddle pan instead of the barbecue.
Lightly toast the ciabatta on the barbecue. Slice open and lay on a lettuce leaf, then a burger and tomato. Season and top with a dollop of paprika mayo. Great with pickled cucumber