# Dice the 
onion at first, peel the 
tomatoes, dice, remove the seeds of the 
banana pepper, and slice finely.
# Put the vegetable oil into a skillet, when it gets hot add the 
onion. When the 
onion softens add 
banana pepper.
# When the colour of the 
banana pepper changes, add the 
tomatoes, sauté for a while, sprinkle salt and black 
pepper, remove from the stove.
# When the sauce with 
tomatoes becomes tepid, boil the macaroni with boiling salty water (10-12 minutes). Pour 1 cup cold water on it just before removing from the stove, drain.
# Add the canned tuna fish into the tepid 
tomato sauce, mix.
# Place the boiled and drained macaronis into the plates, and pour the sauce mixture all over.