Preheat your oven to 375 degrees F and spray a large baking dish with nonstick spray. Set aside.
To a large saute pan, melt 1 tablespoon of the butter over medium-high heat. Add the chicken breasts, and cook for about 3 minutes on each side or until golden brown. Remove from heat and set aside. The chicken will not be cooked through completely. This is OK.
Melt 2 tablespoons of butter in a large saute pan over medium heat. Add the shallot and cook until tender, about 4 minutes. Add the mushrooms and cooked for about 7-8 minutes, or until tender. Stir in the sherry and cook for an additional 2 minutes.Next, add the flour to the pan. Stir frequently, until the flour is golden, about 2 minutes and then slowly whisk in the chicken broth. Cook for about 6 minutes more until thickened and then remove from heat.
To the pan, stir in the rice, parmesan and 2 tablespoons of parsley until fully coated. Season to taste with salt and black pepper.
Pour the mixture into the prepare baking dish and place the chicken on top. Bake the casserole for about 40 minutes or until that chicken has cooked through. Remove from heat and garnish with roasted almonds and additional parsley. Dollop with fresh burrata if desired and enjoy!