How to Make It
Cook pasta according to package directions, omitting salt and fat. Drain and rinse with cold water until cool; drain well.
Combine lemon zest, lemon juice, oil, salt, and pepper in a large bowl, stirring with a whisk.
Place onion in a colander or sieve; rinse with cold water. Drain well.
Add pasta, onion, cucumber, peas, salmon, and dill to dressing; toss gently to combine.