Place half a lettuce leaf on each bun half and top with a salmon burger, some fennel, dill cucumber and a spoonful of lemon and caper mayonnaise.

Set aside. Make the mayonnaise: In a blender or food processor, combine egg and yolk, lemon juice, dill, chives, salt and pepper. With the motor running, slowly drip in both oils, one at a time ...

Air fry at 200℃ for 8 minutes. Turn them over carefully and air fry for another 4 minutes at 200℃. Mix the lemon and dill into the mayonnaise and season with salt and pepper.