Step 1

Combine cheese, heavy cream, egg, cornstarch, olive oil, and lemon zest (if using) in a large bowl. Season lightly with salt and heavily with black pepper and whisk to combine. Set aside.

Step 2

Bring a large pot of salted water to a boil over high heat. Add pasta and cook, stirring frequently to prevent sticking, until cooked but still very firm (not quite al dente), about 45 seconds for fresh pasta or 1 minute less than package directions indicate for dried pasta. Drain pasta into a colander set over a large bowl. Transfer 2 cups (480ml) of cooking water to a liquid measuring cup and discard the rest. Transfer pasta to the now-empty bowl. Add garlic and butter and toss to coat.

Step 3

Whisking constantly, slowly add 1 1/2 cups of pasta cooking water to bowl with cheese mixture. Transfer cheese mixture to the now-empty pasta cooking pot, scraping the bottom to make sure you get everything. Cook over medium-high heat, stirring constantly with a rubber spatula, until mixture comes to a boil and thickens, about 45 seconds. Season sauce to taste with more salt and pepper as desired. Transfer pasta to sauce mixture and turn to coat. Just before serving, stir in more pasta water to thin sauce out as necessary. Serve immediately, sprinkled with minced herbs, black pepper, and cheese, and drizzled with additional olive oil.