Boil a large pot of salted water, cook the 12 oz spaghetti until al dente (8 to 10 minutes), and reserve at least 1 cup of pasta water before draining.

Cook the 6 oz bacon pieces in a large cold skillet over medium heat for 7 to 9 minutes until crisp and golden. Remove with a slotted spoon, leaving the fat in the pan.

Pat the 1 lb shrimp dry, season with 1/4 tsp kosher salt, raise heat to medium-high, and sear in the bacon fat for about 2 minutes per side until pink and curled. Remove and set aside with the bacon.

Reduce heat to low, add the 3 cloves minced garlic to the pan, and stir for 30 to 45 seconds until just golden and fragrant.

Whisk the 4 egg yolks, 1 cup Parmesan, 1/2 tsp black pepper, and 3 tbsp reserved pasta water together in a bowl until thick and smooth.

Turn the heat off, add the drained spaghetti to the pan, toss for 30 seconds in the garlic fat, then pour in the egg mixture and toss continuously for 1 to 2 minutes, adding reserved pasta water a splash at a time until the sauce is silky.

Return the shrimp and bacon to the pan, toss to combine, divide into 4 bowls, and finish with extra Parmesan, cracked black pepper, and the 2 tbsp chopped parsley.