In large skillet, over medium high, heat 1 teaspoon olive oil. Add artichoke and shallots. Cook 4 minutes or until tender, stirring occasionally. Remove from pan and let cool slightly. Mix in cheese, 1/2 teaspoon thyme, 1/8 teaspoon salt, and 1/8 teaspoon pepper.
Wash chicken breasts and pat dry. Slice horizontally to create pocket. Rub remaining salt and pepper evenly over front and back of each breast.
Stuff 2 tablespoons artichoke mixture into each pocket.
Preheat oven to 350°F.
Heat 1 teaspoon olive oil in large skillet over medium high. Place chicken breasts in pan and cook for 6 minutes without moving them. Reduce heat to medium, flip chicken breasts and cook additional 10 minutes or until golden brown.
Remove breasts to oven-proof dish. Cook in oven 15 minutes or until internal temperature reads 165°F on meat thermometer.
While chicken is baking, place pan back on stovetop, add chicken stock and 1/2 teaspoon thyme and bring to boil. Deglaze pan by scraping brown bits from bottom. Stir until bits have dissolved.
In small bowl, whisk lemon juice and cornstarch. Add to bubbling broth. Whisk continuously for 1 minute until sauce is thick.
When chicken is baked, transfer to skillet along with any baking juices. Cover and cook on stovetop for 2 minutes.
To serve, cut stuffed breasts in half. Place on dinner plates and top with sauce. Garnish with chopped parsley and grated lemon zest, if desired.