In a large pot over medium high heat, render the pancetta for about 3-5 minutes.

Once most of the fat is rendered and the pancetta is cooked, remove from heat. 

Transfer the pancetta to a separate plate and discard the rendered fat. 

Return the pot to the stove. Add the chicken broth and garlic.

Cover the pot and bring to a boil. 

Add the spaghetti. Cook the pasta for about 9-10 minutes, until the pasta is al dente and most of the chicken broth has cooked off. 

In a separate bowl, whisk together the half and half, eggs, cheese, salt and pepper. 

Once the chicken broth has cooked off, remove the pot from heat. Discard the garlic.

Quickly stir in the egg mixture until the sauce is thickened. 

Add in the spinach and stir until it wilts slightly.

Toss in the pancetta and parsley. 

Plate and serve - top with red pepper flakes, if desired.