Step by step

Make an incision on one side of the olives and with a teaspoon fill each olive with the stuffing

Tips
Be very careful how you slit open the olives: do it so that the cut does not allow the filling to leak out, nor end up with an olive cut in half.
Trivia
Latin authors such as Marziale and Catone cited the special varieties of olives that were used to prepare this delicacy.