Directions

1. Preheat oven to 400°F. Cook bacon in a large, deep skillet over medium heat, stirring often, until crispy, about 7 minutes. Remove with a slotted spoon to a paper-towel-lined plate, reserving drippings in the pan.
2. Add 2 tablespoons butter to the drippings in the pan; cook over medium-high heat until melted, about 30 seconds. Add half of the chicken and 1/4 teaspoon pepper. Cook, stirring often, until the chicken is lightly browned and cooked through, about 6 minutes. Transfer to a plate. Repeat the procedure with the remaining chicken and 1/4 teaspoon pepper.
3. Without wiping the pan, melt the remaining 2 tablespoons butter over medium-high heat. Add onion, white and light green parts of scallions and chopped jalapeños; cook, stirring often, until softened, about 6 minutes. Sprinkle flour over the vegetables, stirring to coat; cook, stirring constantly, for about 1 minute. Add broth and milk; cook, stirring constantly, until thickened, 1 to 2 minutes. Add cream cheese; cook, stirring constantly, until melted, about 1 minute. Remove from heat; stir in the chicken, mozzarella and salt.
4. Spoon the mixture into a 9-by-13-inch baking dish. Sprinkle with breadcrumbs and cover with foil. Bake for 10 minutes. Remove the foil and bake, uncovered, until the topping is golden brown and the mixture is bubbling throughout, about 15 minutes more. Sprinkle with the reserved bacon, dark green parts of scallions and jalapeño slices. Serve hot.