Turkey-Herder's Pie

Melt 3 tablespoons butter in heavy large saute pan over medium heat. Add leeks and dry tarragon; cover and cook until leeks are tender but not brown, stirring occasionally, about 8 minutes. Add turkey and 1 teaspoon salt. Cook until turkey is no longer pink, breaking up meat with back of spoon, about 7 minutes. Sprinkle flour over turkey and cook 3 minutes, stirring often. Gradually stir in broth, wine and 1/2 teaspoon pepper. Add vegetables and simmer uncovered until liquid reduces slightly and thickens, stirring often, about 5 minutes. Season turkey mixture to taste with salt and pepper. DO-AHEAD TIP: Turkey mixture can be prepared 1 day ahead. Cool, cover and refrigerate, returning to room temperature before proceeding. Position rack in upper third of oven and preheat to 350 degrees F. Lightly butter shallow 13x9-inch rectangular baking dish. Cook potatoes in large pot of boiling salted water until very tender, about 25 minutes. Drain; return potatoes to same pot. Set over low heat and stir potatoes 1 minute to remove any excess water. Mash potatoes. Melt remaining 4 tablespoons butter in heavy small saucepan over low heat. Add fresh tarragon and cook 1 minute. Add half and half; bring just to simmer. Gradually stir into potatoes and beat with spoon until smooth. Season to taste with salt and pepper. Cool until almost room temperature. Mix in eggs. Spread turkey mixture into prepared baking dish. Spread potato mixture evenly over turkey and to edges of dish; smooth top. Using handle of wooden spoon, score shallow diamond pattern over potatoes. Bake until filling bubbles and potato topping is firm and lightly browned, about 1 hour. Cool 5 minutes. Cut into squares and serve hot. Recipe created exclusively for Cooking.com by Michael McLaughlin.