Bring a large pot of heavily salted water to a boil. While the water is heating, toast the pine nuts in a small, dry skillet over medium heat until golden and fragrant, about 2-3 minutes, tossing frequently. Remove from skillet immediately and set aside.

In a medium bowl, combine the whole milk ricotta, lemon zest, lemon juice, 1/2 cup of grated Parmesan cheese, and red pepper flakes (if using). Whisk until smooth and creamy. Season generously with salt and pepper.

Add the linguine to the boiling water and cook according to package directions until al dente.

About 3 minutes before the pasta is done, melt the butter in a large skillet or pan over medium heat. Add the minced garlic and cook until fragrant, about 30-60 seconds. Be careful not to let it brown.

Before draining the pasta, carefully reserve about 1.5 cups of the starchy pasta water. Drain the pasta and add it directly to the skillet with the garlic butter. Turn off the heat.

Add the ricotta mixture to the pasta in the skillet. Pour in about 1/2 cup of the reserved pasta water to start. Toss everything together vigorously using tongs. The residual heat will melt the cheeses and the starchy water will help create a smooth, creamy sauce that coats every strand.

Continue to toss, adding more pasta water a tablespoon at a time, until the sauce reaches your desired consistency. It should be creamy, not watery or thick.

Fold in the fresh arugula until it just begins to wilt. Taste and adjust seasoning with more salt and pepper if needed.

Serve immediately in warm bowls, garnished with the toasted pine nuts, an extra sprinkle of Parmesan cheese, and a drizzle of good quality extra virgin olive oil.