- 2 tablespoons extra-virgin olive oil, divided
- 2 pounds ground bison meat* or ground beef
- 8 ounces mushrooms, finely chopped
- 1 tablespoon tomato paste
- 3 tablespoons chopped fresh thyme
- 2 tablespoons all purpose flour
- 2 cups low-salt chicken broth
- 2 cups diced peeled carrots
- 2 cups frozen green peas, thawed
- 2 pounds Yukon Gold potatoes, peeled, cut into 3/4-inch pieces
- 1 large head of cauliflower (about 1 1/2 pounds), cored, coarsely chopped
- 1/2 cup (1 stick) butter, room temperature
- 2 1/2 cups freshly grated Parmesan cheese, divided (about 8 ounces)
- 3 tablespoons finely grated peeled fresh horseradish or prepared horseradish
- Extra-virgin olive oil for drizzling
- Chopped fresh Italian parsley
Heat 1 tablespoon oil in large pot over high heat. Add bison; sauté until browned, about 5 minutes. Using slotted spoon, transfer bison to bowl. Add 1 tablespoon oil to pot, then add onions and mushrooms. Sauté until soft, about 7 minutes. Add tomato paste; stir 2 minutes. Add thyme and flour and stir 1 minute. Add broth and wine and bring to boil. Return bison to pot. Reduce heat; simmer until mixture thickens and is reduced to 5 1/2 cups, about 13 minutes. Season with salt and pepper.
Cook carrots in boiling salted water just until slightly softened, about 2 minutes. Drain. Transfer to bowl; add peas. Set aside.
Cook potatoes and cauliflower in large pot of boiling salted water until tender, about 10 minutes. Drain, reserving cooking liquid. Transfer vegetables to processor and puree, adding 1 1/2 cups reserved cooking liquid, 1/4 cup at a time, until mixture is smooth. Transfer mixture to bowl; stir in butter and cream, then 2 cups Parmesan cheese and horseradish. Season potato topping to taste with salt and pepper.
Preheat oven to 400°F. Butter 15x10x2-inch glass baking dish. Spread meat mixture in dish. Top with vegetables. Spread potato topping over, covering completely and swirling with knife to create peaks, if desired. Drizzle lightly with oil; sprinkle with 1/2 cup Parmesan. DO AHEAD Can be made 1 day ahead. Chill uncovered until cold, then cover and keep chilled. Let stand at room temperature 2 hours before continuing.
Bake pie uncovered until heated through and top is lightly browned, about 50 minutes. Sprinkle with parsley and smoked paprika.
*Ground bison meat is available at natural foods stores, specialty foods stores, and some farmers' markets. You can also find a local source by going to bisoncentral.com.
**Sometimes labeled Pimentón Dulce or Pimentón de La Vera Dulce; available at some supermarkets, at specialty foods stores, and from tienda.com.