Fill a 5 qt saucepan halfway with water and add a large pinch of salt. Bring to a boil over high heat. Add the orzo and return to a boil. Reduce heat to medium-low and cook the pasta for about 2 minutes less than the box indicates. You want the orzo to be just cooked, but still firm. While the pasta is cooking, add the frozen peas to the bottom of the colander that you will be using to drain the orzo.
When the pasta is cooked properly, drain it over the frozen peas. This will defrost and cook the peas just slightly. Rinse the pasta and peas under cold water to stop the cooking process then set aside.
In a medium mixing bowl, whisk together the lemon zest, lemon juice, olive oil, chopped dill and salt. Add the pasta and peas and fold until completely combined.
Stir in crumbled feta to combine then cover the bowl with plastic wrap and chill for at least 1 hour. Before serving, give the salad one last stir to redistribute the dressing and break up any pasta that stuck together. Taste for seasoning and add salt and pepper if needed. Serve this salad cold or at room temperature. Enjoy!