Use colander to strain 1 (14.5 ounce) can diced tomatoes, reserving the juice.
Rub 2 chicken breast with 1 tablespoon olive oil, 1 teaspoon salt, 1 teaspoon ground black pepper, and the leaves of one of the 3 sprigs fresh rosemary.
Add 2 tablespoons butter to skillet and melt over medium heat, turning skillet to coat completely.
Add 2 teaspoons minced garlic to skillet and stir until golden brown.
Pour tomato juice into skillet and bring to a simmer.
Add chicken breast to skillet and brown on each side, around 3-5 minutes.
Add diced tomatoes to skillet, then place skillet in oven and bake at 350 degrees Fahrenheit for 10 minutes, or until chicken has reached an internal temperature of 165 degrees Fahrenheit. (If your skillet is not oven-safe, transfer contents into an oven-safe baking dish before baking.)
Serve on top of prepared quinoa (or other grain). Season with salt, pepper, lemon juice and/or zest, and remaining sprigs of rosemary to taste, before serving.