Bring a large pot (about 4–5 liters) of water to a rolling boil and add 1 tablespoon kosher salt. Cooking the pasta in generously salted water seasons the noodles from the inside and enhances the overall flavor of the dish. Keep the pot uncovered and set a colander nearby.

When the water returns to a boil, add the linguine and cook until al dente according to package instructions (about 8–10 minutes). Reserve 3/4 cup (180 ml) of the pasta cooking water before draining. Reserving starchy pasta water lets you adjust sauce thickness and helps the sauce cling to the noodles.

While the pasta cooks, pat the shrimp very dry with paper towels and season lightly with a pinch of sea salt and freshly ground black pepper. Dry shrimp sear more cleanly and develop better texture; moisture causes steaming instead of browning.

Heat a large sauté pan over medium-high heat. Add the olive oil and swirl to coat. Add the shrimp in a single layer and sear for about 1.5–2 minutes per side (total 3–4 minutes), until pink, just opaque and slightly golden at the edges. Cooking shrimp quickly over high-ish heat gives them a snappy texture; avoid overcooking which makes shrimp rubbery. Transfer shrimp to a plate and keep warm.

Lower the heat to medium, add the butter to the same pan and let it melt until it forms small foamy bubbles. Add the minced garlic and red pepper flakes and sauté for 30–45 seconds, stirring constantly. Toasting the garlic briefly in butter releases its aroma without burning; the red pepper flakes bloom and release spicy oils for a background heat.

Add the chopped winter greens to the pan and sauté for 1–2 minutes until wilted but still bright. Adding the greens to the warm butter-garlic mixture lets them soften while picking up the garlicky flavor; cook just enough to retain color and slight bite.

Pour in the reserved 1/4–1/2 cup (60–120 ml) pasta water (start with 1/4 cup) and the lemon juice, scraping up any browned bits from the bottom of the pan. The starchy water helps emulsify a light sauce with the butter and oil; lemon brightens and balances richness. Simmer for 1 minute to integrate flavors.

Return the seared shrimp to the pan along with the drained linguine. Toss vigorously for 30–60 seconds to combine, adding more reserved pasta water as needed to create a glossy, slightly saucy coat on the noodles. Tossing over heat allows the pasta to absorb flavor and the sauce to cling.

Remove the pan from the heat. Add lemon zest and 2 tablespoons toasted breadcrumbs, then adjust seasoning with salt and pepper. The lemon zest adds concentrated citrus aroma; the toasted breadcrumbs add crunch and a toasty, nutty contrast to the tender pasta and shrimp.

Divide the linguine between two warmed plates, sprinkle with remaining breadcrumbs if desired, and finish with chopped parsley and an extra drizzle of olive oil or a small pat of butter for richness. Serve immediately. Finishing touches add freshness (parsley) and shine (oil/butter).