Step 1

Preheat the oven to 350 degrees F. Line a large rimmed baking sheet with parchment paper. Lay the chicken breasts flat on the baking sheet. Starting from one side, cut a deep slit (or pocket) into each chicken breast, parallel to the baking sheet, leaving three sides intact. Try to make the cut even so the attached edges are all about 1/2-inch thick.

Step 2

Chop the salami and olives. Shred the cheeses.

Step 3

Into a mixing bowl, measure both kinds of cheese, diced salami, chopped olives, and capers. Mix well.

Step 4

Stuff the mixture evenly into the chicken breasts, turning them upright, so the stuffing is facing up. Sprinkle the tops with ground black pepper.

Step 5

Bake for 25 minutes, until the chicken breasts have cooked through and the filling is bubbly. Serve warm.