Bring a large pot of salted water to a boil and cook the spaghetti.
In a mixing bowl, whisk together the eggs and grated Parmesan cheese until well combined. Season with a pinch of salt and black pepper. Set aside.
In a large skillet, add Olive Oil over medium heat. Add the guanciale slices and cook until crispy and golden brown. Remove the guanciale from the skillet and set aside, leaving the rendered fat in the pan.
Reduce the heat to low, and add the cooked spaghetti to the skillet, tossing it in the rendered fat and garlic until well coated.
Remove the skillet from heat and pour in the egg and Parmesan mixture. Quickly and vigorously toss the spaghetti in the mixture, ensuring it is evenly coated.
The residual heat from the spaghetti will cook the eggs, creating a creamy sauce. Be careful not to overcook the eggs; you want them to be smooth and creamy, not scrambled.
Crumble the crispy guanciale slices over the spaghetti carbonara and toss again to distribute.
Taste and adjust the seasoning with salt and black pepper, if needed.
Serve the Spaghetti Carbonara immediately, garnished with additional grated Parmesan cheese if desired.
Enjoy your homemade Spaghetti Carbonara! Buon Appetito!