Prepare all the burger ingredients apart from the meat:
– 
Prepare 1  
avocado, slice fairly thickly and drizzle with lime juice.
– Cut 50 g  Cheddar cheese into thin shavings with a 
vegetable peeler.
– 
Prepare 1  
onion and slice thinly.
– Rinse and dry 8 leaves  fresh spinach.
– Pick the coriander (cilantro) leaves off the stalks.