1. Preheat oven to 400°. Cook bacon in a large deep skillet over medium-high heat until crisp. Remove from pan; crumble and set aside.
2. Add mushrooms and next 4 ingredients to skillet; cook, stirring often, 8 minutes or until mushrooms are lightly browned and all liquid has evaporated. Stir in broth and next 4 ingredients, and bring to a boil. Cover, reduce heat, and simmer 6 to 10 minutes or until potatoes are tender.
3. Whisk together half-and-half and flour in a small bowl; add to skillet and cook, stirring constantly, 3 minutes or until mixture comes to a boil and thickens slightly. Add salmon, and cook 1 to 2 minutes or until opaque. Remove from heat, and stir in chives and reserved bacon. Spoon mixture into a lightly greased 2 1/2-quart baking dish.
4. Place 1 phyllo sheet on a work surface. (Cover remaining phyllo with a damp kitchen towel to prevent drying.) Brush lightly with melted butter, and sprinkle evenly with about 1 tablespoon cheese. Top with another phyllo sheet. Repeat with remaining phyllo, butter, and cheese.
5. Place stacked phyllo on top of salmon mixture, and tuck in corners. Place baking dish on a baking sheet. Bake 15 minutes or until golden brown and bubbly.