How to Make It
Cook pasta according to package directions, omitting salt and fat. Drain, reserving 1/2 cup cooking liquid. Cover pasta to keep warm.
While pasta cooks, pat shrimp dry with paper towels; season with pepper and 1/4 teaspoon salt. Heat half of the olive oil in a large nonstick skillet over high. Add shrimp; cook, stirring often, until cooked through, 3 to 4 minutes. Transfer to a plate; cover to keep warm. (Do not wipe skillet clean.)
Reduce heat to medium-high. Add leek, garlic, remaining oil, and remaining 1/2 teaspoon salt. Cook, stirring often, until leek is slightly tender, 2 to 3 minutes. Add peas, cream, lemon zest, lemon juice, and reserved 1/2 cup cooking liquid. Reduce heat to medium; simmer until sauce thickens slightly, 2 to 3 minutes. Add shrimp to skillet; toss to coat.
Divide pasta among 4 bowls; top evenly with shrimp and sauce. Sprinkle with dill, and serve immediately.