Grease a 15- x 10- x 1-inch jellyroll pan.
Line with wax paper; grease again.
Sift first 4 ingredients together; set aside.
Beat egg whites (at room temperature) at high speed of an electric mixer until foamy.
Gradually add sugar, beating until soft peaks form; set aside.
Beat egg yolks until thick and lemon colored; stir in flavorings.
Fold yolk mixture into egg white mixture; then gently fold in flour mixture.
Spread evenly in prepared pan.
Bake at 350° for 12 minutes.
When cake is done, immediately loosen from sides of pan and turn out onto a damp towel.
Peel off wax paper.
Starting at wide end, roll up cake and towel together; cool 30 minutes on wire rack, seam side down.
Unroll cake; remove towel.
Spread ice cream over cake.
Gently roll cake back up; place on a large baking sheet, seam side down.
Freeze until ice cream is firm.
Frost cake with chocolate frosting; freeze until serving time.
Sprinkle with pistachios.