Cook the pasta:
In a large pot of salted water, cook the spaghetti “al dente” according to the package instructions.
Reserve about 150 ml of the pasta cooking water — it will be used later for the sauce.

Prepare the pancetta:
In a large pan over medium heat, heat the olive oil.
Add the diced bacon (or pancetta) and cook until crispy (about 4–5 minutes).
Optionally, add a clove of garlic (lightly crushed, not chopped) for extra aroma, then remove it once it becomes fragrant.

Prepare the creamy sauce:
In a bowl, whisk the eggs and egg yolks, then add the grated Belgrader cheese.
Mix well until a thick, creamy mixture forms.
Add a generous amount of freshly ground black pepper — this is the key seasoning for authentic carbonara.

Combine the pasta and pancetta:
Add the drained spaghetti directly into the pan with the pancetta (do not rinse the pasta).
Mix well so the pasta absorbs the oil and fat from the pan.
Remove the pan from heat (this is important so the eggs don’t turn into scrambled eggs).

Add the sauce:
Pour the egg and Belgrader mixture over the hot spaghetti.
Stir quickly and vigorously until the sauce thickens and evenly coats the pasta.
If needed, add a bit of the reserved pasta water to achieve a perfectly creamy consistency.