Chicken Breasts Stuffed with Pareve Ricotta Cheese and Olives with Balsamic Glaze

Serves 4 but doubles easily
This chicken is great warm or at room temperature. It works so well with the new Tofutti Pareve Ricotta Cheese. It is great accompanied by garlicky spinach or green beans.
4 boneless, skinless chicken breast halves (about 1-1/2 lb. total)
Kosher salt and freshly ground black pepper
4 ounces pareve tofutti ricotta cheese
2 tablespoons coarsely chopped pitted Kalamata olives
2 teaspoons finely grated lemon zest (from 1 large lemon), divided
1-1/2 teaspoons minced fresh rosemary
1/2 cup flour
6 tablespoons margarine, cut into 6 pieces
1 tablespoon olive oil
3 tablespoons minced shallots
1-1/2 tablespoons balsamic vinegar
2 tablespoons chicken broth
With a boning knife, cut a wide pocket into the thickest part of each chicken breast half, taking care not to cut all the way through. Season the chicken evenly on both sides with 1/2 teaspoon salt and 1/4 teaspoon pepper.
In a small bowl, mix the tofutti ricotta cheese, olives, and 1 teaspoon each lemon zest and rosemary. Stuff the pockets with the ricotta mixture and pin each shut with two toothpicks. Spread the flour in a shallow bowl and dredge the chicken in the flour, shaking off the excess.
Heat 1 tablespoon of the margarine and the oil in a 12-inch heavy-duty skillet over medium-high heat until the foam from the butter subsides. Add the chicken and cook, flipping once and adding another 1 tablespoon margarine halfway through cooking, until golden-brown and cooked through (reduce the heat to medium if necessary), 14 to 16 minutes total. Transfer to plates and remove the toothpicks.
While the chicken cooks, melt 1 tablespoon margarine in an 8-inch skillet over medium-high heat. Add the shallots and cook, stirring, until softened, about 3 minutes. Add the vinegar and boil until syrupy, about 3 minutes. Add the broth and boil for 1 minute more. Off the heat, whisk in the remaining 3 tablespoons margarine, remaining 1 teaspoon lemon zest, and remaining 1/2 teaspoon rosemary. Serve the chicken drizzled with the sauce.