Preheat oven to 375F. Butter 13x9x5/8-inch jelly roll pan. Line pan with waxed paper; butter paper. Mix first 5 ingredients in large bowl. Mix in eggs and pumpkin. Pour batter into prepared pan, spreading evenly. Bake until tester inserted into center of cake comes out clean, about 15 minutes. Lay kitchen towel on work surface; dust with 2 tablespoons powdered sugar. Cut around pan sides to loosen cake. Turn out cake onto sugared towel, waxed-paper side up. Fold 1 side of towel over 1 long side of cake, then roll up cake jelly roll style. Cool cake. Combine cream cheese, 1 cup powdered sugar, butter and vanilla in medium bowl; beat to blend. Mix in walnuts. Unroll cake; leave on towel. Peel off paper. Spread cream cheese filling evenly over cake. Using towel as, roll up cake and place seam side down on platter. Trim ends of cake. Dust cake with powdered sugar. (Can be prepared 1 day ahead. Cover and refrigerate.) Cut cake crosswise into 1-inch-thick slices and serve. Serves 10 to 12. Bon Appetit July 1995 Per serving: 2530 Calories (kcal); 117g Total Fat; (40% calories from fat); 34g Protein; 346g Carbohydrate; 878mg Cholesterol; 1480mg Sodium Food Exchanges: 0 Grain(Starch); 5 Lean Meat; 0 Vegetable; 0 Fruit; 21 Fat; 22 1/2 Other Carbohydrates Converted by MM_Buster v2.0n.