Preheat the oven to 375 degrees F.
For the orzo: Whisk together the stock, butter, salt, cornstarch, thyme, lemon zest and juice and garlic in a bowl. Mix in the orzo.
For the chicken: Sprinkle each chicken breast with the coriander, salt and pepper.
Pour the broth and orzo mixture into a glass 9-by-13-inch baking dish. Add the chicken breasts and lemon slices to the dish alternately between the two.
Bake, uncovered, until the chicken registers an internal temperature of 165°F, 35 to 40 minutes. Garnish with some chopped thyme.
Yum!
