Step #1. Prepare the vinaigrette by combining tablespoons of olive oil and other ingredients on a glass jar with a tight-fitting lid. Cover and shake vigorously until thoroughly combined. Set aside.
On a cutting board, cut the breasts in half horizontally (with the blade parallel to the counter). Arrange both halves on the sheets of plastic wrap or wax paper in a single layer.
Step #3. To adjust the size of thick slices, cover the mat with a second sheet of plastic wrap or wax paper and pound to ¼” thickness with a meat pounder or rolling pin.