1) Peel the potatoes and carrots, rinse both and chop them into small dice. Fill a large saucepan with water, add a dash of salt and place it over high heat until boiling. Then add the diced potatoes.
2) Cook for 3 minutes. Then add the carrots.
3) Cook for 4 more minutes. Now add the frozen peas.
4) Cook for another 2 minutes. Then immediately strain the cooked vegetables and rinse them under ice cold running tap water to stop the cooking process. Let them drain a little.
5) Pour the warm carrots, potatoes and peas in a large mixing bowl. Add the mayonnaise. Season with a little pepper and salt.
6) Drain the canned tuna and also add it to the bowl.
7) Stir well. Then check the seasoning and add extra pepper or salt to taste if necessary. Serve the ensalada rusa at room temperature, not cold.