Start cooking the pasta according to box directions.
While the pasta cooks, add the mayonnaise, ranch mix, salt and pepper, and tuna to a large mixing bowl. Break up the tuna with a fork, then mix everything together well. Taste and adjust seasoning.
Mix in the frozen peas.
When the pasta is cooked, drain and rinse with cold water. Don’t worry about the pasta being completely cold. The frozen peas will help chill the pasta as the slightly warm noodles thaw them, leaving the salad perfectly cooled.
Stir everything together to combine. Check seasoning again, then serve and enjoy.