You do:

• 400 gr pens
• 160 gr diced pancetta
• 1 clove of garlic
• 1 eggs
• 3 yolks
• Parmesan, as 1 dl grated on the fine side
• Pecorino, as 1 dl grated on the fine side
• Black Pepper
• A little olive oil

Do this:

1. Mix cheese and eggs and whisk to a sauce, pour in a little black pepper to taste
2. Put the pancetta in a cold frying pan and let the fat render, ie melt on medium heat
3. Remove the fat, pour it into a glass and let it cool a bit and then pour it into the sauce
4. Pour a little pasta water into the sauce
5. Turn off the stove and mount the pasta in the pancetta ( in the frying pan with pancetta)
6. Pour in some pasta water and stir / toss for a minute
7. Mount the sauce in the pasta / pancetta
8. Mix everything and serve immediately