- 2 1/2 pounds green beans, preferably haricot verts, trimmed
- 1 teaspoon kosher salt, plus more
- 3 lemons
- 2 large leeks, white and light-green parts only
- 1 1/2 cups olive oil
- 1/2 teaspoon freshly ground black pepper
- Cook green beans in a large pot of boiling salted water until crisp-tender, 5–7 minutes. Drain, then immediately transfer to a large bowl filled with ice water. Drain again and pat dry.
- Meanwhile, zest lemons to yield 1 Tbsp. zest. Juice lemons to yield 1/4 cup juice, then slice any remaining lemons into wedges. Cut leeks crosswise into 4″ sections, then thinly slice lengthwise into matchsticks.
- Heat oil in a large deep-sided skillet over medium-high until shimmering. Cook half of leeks, stirring occasionally, until lightly golden brown and crispy, about 5 minutes. Using a slotted spoon, transfer to paper towels; season with salt. Repeat with remaining leeks; reserve oil in skillet.
- Cook green beans, pepper, lemon zest, and remaining 1 tsp. salt in reserved oil over medium heat, tossing occasionally, just until warmed through, about 5 minutes. Add lemon juice and toss to coat, then transfer to a platter. Drizzle about 1/2 cup oil from pan over; reserve remaining oil for another use. Top with leeks and serve with lemon wedges alongside.
- Green beans can be blanched 1 day ahead; let dry, then transfer to an airtight container and chill.