Preheat oven to 350 degrees F (175 degrees C). Lightly oil a deep, round baking dish.
Melt the butter in a large saucepan over medium heat. Add the onions and cook until translucent, about 5 minutes. Add the minced garlic and cook for one minute. Sprinkle the flour into the saucepan; cook and stir until mixture darkens slightly, about 2 minutes. Whisk in the Swanson(R) Unsalted Chicken Stock. Bring to a simmer over medium-high heat; reduce heat to medium. Cook and stir until mixture thickens, about 3 minutes.
Stir in baby kale; cook until wilted. Add the cannellini beans, chicken, and plum tomatoes; stir. Season with oregano, basil, salt and pepper to taste. Pour mixture into prepared baking dish.
Place pie crust on top of the chicken mixture. Tuck under or trim edges that extend over the sides. Make several slits in the crust with the tip of a sharp knife to allow steam to escape.
Bake in preheat oven until crust has browned and mixture is bubbly, about 30 minutes.
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