Walnut-Pear Sour Cream Cake
["1 c. broken walnuts", "1/3 c. packed brown sugar", "1 tsp. cinnamon", "1/4 c. butter", "1/3 c. flour", "2 medium pears, peeled and diced (2 c.)", "2 tsp. lemon juice", "1 3/4 c. flour", "3/4 tsp. baking powder", "1/2 tsp. baking soda", "1/4 tsp. salt", "1/2 c. butter, softened", "1 c. sugar", "1 tsp. vanilla", "2 eggs", "1 (8 oz.) carton sour cream"]
["Preheat oven to 350\u00b0.", "Grease 9-inch spring-form pan. Combine 1 cup nuts, brown sugar and cinnamon.", "For topping, cut 1/4 cup butter and 1/3 cup flour for coarse crumbs.", "Stir in 1/4 cup of nut mixture.", "Set both mixtures aside.", "Toss pears with lemon juice and set aside.", "Mix the flour, baking powder, soda and salt; set aside.", "In large bowl beat the 1/2 cup butter, sugar and vanilla.", "Add eggs one at a time.", "Add flour mixture and sour cream alternately to batter.", "Beat on low speed after each addition.", "Spread 2/3 mixture in prepared pan.", "Sprinkle with nut mix and layer pears on top.", "Spread with rest of batter and sprinkle topping.", "Bake 10 minutes and sprinkle with 1/2 cup more walnuts.", "Bake 50 minutes more."]
["walnuts", "brown sugar", "cinnamon", "butter", "flour", "lemon juice", "flour", "baking powder", "baking soda", "salt", "butter", "sugar", "vanilla", "eggs", "sour cream"]