Start by washing the potatoes very well and then remove their skin, when you have finished, place them on a big bowl with water and leave them there for 5 minutes, then remove the water and place them on a dry bowl.
Take a pot and pour in half of the olive oil and fry the chopped onion for about 2-3 minutes, then add the frozen peas and mix well until, they are no more frozen, then add the potatoes. Add water, so as to cover all the peas and potatoes, add salt and pepper and leave them to boil.
In the meanwhile take another pot and place in it the Sirloin steaks, then pour water on the pot, until you cover the steaks and also add salt and pepper, leave the steaks to boil until they are well boiled and soft.
When the potatoes and peas are ready, place them on the plates, like in the picture and when the steaks are boiled, add then on the plates and enjoy your meal.