Drain the cans of tuna into a fine sieve with a bowl underneath, gently shake the sieve to remove any excess oil, transfer the tuna into a large bowl
Cut the cucumber into bite-sized slices, cut the red onion into bite-sized slices and roughly chop the bell pepper, add the ingredients into the bowl with the tuna
Cut the avocados in half, remove the pit and scoop out the flesh, cut the avocado flesh into large chunks and then add into the bowl
Squeeze in the lemon juice over the ingredients, along with 2 tbsp (30 ml) of the reserved olive oil from the canned tuna, add in the parsley and season with sea salt & black pepper, gently mix together
Cover with saran wrap and add into the fridge for a couple of hours or serve at room temperature, enjoy!