To begin the pesto, grate each cheese and toss to combine. Using a mezzaluna knife (or a chefs knife or food processor), begin by chopping the garlic.
Add the basil in three portions, making sure to incorporate each amount before adding the next. Do the same with the pine nuts, incorporating them in two batches. Once the mixture is finely chopped, gather everything together and incorporate the cheese in two batches, finely chopping everything together. Transfer to a bowl and add the olive oil. Add enough oil until you reach the consistency you like.
Lastly, taste the pesto for seasoning. You may not have to add any salt. It will depend on how salty the cheese is.
- 1/3 cup pecorino cheese
- 2/3 cup Parmigiano-Reggiano
- 1 large garlic clove
- 1 cup packed, fresh basil leaves (approx. 2 bunches)
- 1/4 cup pine nuts
- 1/2 cup extra-virgin olive oil
- kosher salt (to taste)