Ingredients

• 2 tablespoons (1/4 stick) butter
• 1 large fennel bulb, trimmed, halved, thinly sliced crosswise (about 3 cups)
• 1/2 cup sliced shallots (about 2 medium)
• 2 tablespoons all purpose flour
• 1 1/2 cups vegetable broth
• 1 1/2 pounds halibut fillets, cut into 1-inch cubes
• 1 6-ounce package baby spinach
• 3 1/2 cups warm mashed potatoes

Instructions

1. Preheat broiler. Melt butter in heavy large saucepan over medium heat. Add fennel and shallots. Cover; cook until tender, stirring occasionally, about 8 minutes. Sprinkle with flour, salt, and pepper. sauté 2 minutes. Add broth; bring to boil, stirring often. Add fish and spinach. Cover; simmer over medium heat until fish is almost cooked through, about 4 minutes.
2. Transfer fish mixture to 11x7x2-inch baking dish. Spoon mashed potatoes over, covering completely. Broil until filling bubbles at edges and potatoes are brown in spots, about 4 minutes. Serve.