4 bunches of basil (100 gr)
The reason Italians prefer Ligurian basil, is because of its discreet flavor and the  absence of a minty taste, therefore try finding something similar or rather cultivate it on your own. 
Discard all stems, gently rinse all leaves under cold water, and let them dry.

2 cloves if garlic
Cut them in half, and remove the green ste in the center.

1 teaspoon pine nuts
Try avoiding the common Chinese nuts sold at super markets.  Prefer Mediterranean ones, they might be more expensive but they are definitely finer.

3 tablespoons Parmigiano Regiano
3 tablespoons Pecorino, preferably Sardinian.
Both grated.

1 glass extra virgin olive oil
You need to get the best quality, light, smooth, not strong and sharp.

Some salt
Sea salt, preferably coarse.
You only need salt to protect the basil from oxidation, therefore be mingy.