Step 1

1 Fill a large pot with about 3 quarts of water, place over high heat and bring to a boil

Step 2

2 While the water is coming to a boil, prepare the rest of the ingredients

Step 3

3 Using the large, shallow bowl you’ll be serving the pasta in, combine the whole egg, egg yolk

Step 4

4 Parmigiano-Reggiano, pecorino Romano and parsley, if using

Step 5

5 Season with a little salt and a generous amount of black pepper

Step 6

6 Using a fork, whisk until thoroughly combined but not so much that you beat a lot of air into the mixture

Step 7

7 In a 10-inch skillet over medium-high heat, combine the pancetta, olive oil and butter and cook until the pancetta begins to brown but not long enough to make it crisp, 4 to 5 minutes

Step 8

8 Add the wine and cook until reduced by half, scraping up any brown bits on the bottom of the pan, 1 to 2 minutes

Step 9

9 Remove from the heat

Step 10

10 Carefully remove about 1 tablespoon of the rendered fat and add it to the egg mixture to begin to temper the sauce, quickly whisking again with the fork

Step 11

11 When the water comes to a boil, season with 1 tablespoon salt, add the spaghetti and stir until all the strands are submerged

Step 12

12 Cook according to the package instructions, stirring occasionally, until the pasta is al dente, or mostly done with just a little bit of bite left

Step 13

13 When the pasta is almost ready, return the skillet with the pancetta to medium-high heat

Step 14

14 When the pasta is done, drain, reserving 1 cup of the water, and transfer it to the serving bowl, tossing vigorously with tongs or stirring with a wooden spoon until thoroughly coated with the egg mixture

Step 15

15 Pour half of the pancetta into the bowl, toss again, and add pasta water as needed to achieve your preferred sauce consistency

Step 16

16 Add the remaining pancetta without stirring so you have plenty visible on top

Step 17

17 Serve immediately

Step 18

18 NOTE: Use pasteurized eggs, such as Davidson’s brand, if you are concerned about eating undercooked eggs