Place 1 tablespoon pine nuts in a small skillet over medium-low heat. Stir frequently until fragrant and lightly golden, about 2–3 minutes. Remove from heat and let cool.

Make pesto in a food processor

Add basil leaves (packed), cooled toasted pine nuts, garlic cloves, grated Parmigiano-Reggiano, lemon juice, 3/4 teaspoon kosher salt, and 1/4 teaspoon black pepper to a food processor. Pulse several times to begin breaking down ingredients.

Emulsify with oil

With the processor running, slowly drizzle in 1/2 cup extra-virgin olive oil until the mixture forms a smooth but slightly textured emulsion. Stop and scrape down the sides as needed. Taste and adjust seasoning with additional salt or lemon juice if desired. If pesto is very thick, thin with 1–2 tablespoons reserved pasta water later during assembly.

Pasta & Assembly

Bring salted water to a boil

Bring a large pot of water to a rolling boil. Add 1 tablespoon salt.

Cook pasta

Add 12 oz dried linguine or spaghetti and cook according to package directions until al dente, typically 8–10 minutes. Before draining, reserve 1 cup of the starchy cooking water, then drain the pasta.

Combine pasta and pesto

Return hot drained pasta to the pot off the heat. Add 3/4–1 cup prepared pesto and 1/3–1/2 cup reserved pasta water. Toss vigorously with tongs or two forks to coat the pasta evenly. The starchy water will loosen and bind the pesto to the pasta; add additional water 1 tablespoon at a time if needed to reach a silky sauce that clings to the noodles.

Add tomatoes and greens

Gently fold in halved cherry tomatoes and baby arugula (if using) until wilted slightly from the pasta's heat. Taste and adjust with salt, pepper, or a squeeze of lemon if needed.

Plate and garnish

Divide pasta among 4 plates (servings). Finish each serving with a drizzle of 1 teaspoon extra-virgin olive oil, a sprinkle of toasted pine nuts, about 1 tablespoon grated Parmigiano-Reggiano, and a little lemon zest if using.