DIRECTIONS

In a small bowl, combine milk and poppy seeds; let stand for 1 hour. In a large bowl, cream butter and sugar until light and fluffy. Combine the flour, baking powder and salt; add to creamed mixture alternately with poppy seed mixture, beating well after each addition.
    In another large bowl with clean beaters, beat egg whites until soft peaks form; fold into batter. Pour into two greased and floured 9-in. round baking pans.
    Bake at 350° for 15-20 minutes or until a toothpick inserted near the center comes out clean. Cool for 10 minutes before removing from pans to wire racks.
    For filling, in a small heavy saucepan, combine the sugar, sour cream and egg yolks. Cook and stir over low heat just until mixture begins to simmer and reaches 160° or is thick enough to coat the back of a metal spoon. Remove from the heat; add nuts and vanilla. Transfer to a bowl; cover with plastic wrap and refrigerate until completely cooled.
    For frosting, in a small bowl, beat the butter, confectioners' sugar and cocoa until fluffy. Add coffee, 1 tablespoon at a time, until mixture achieves spreading consistency.
    Place one cake layer on serving plate; spread with filling. Top with second layer. Spread frosting between layers and over top and sides of cake. Store in the refrigerator. Yield: 10-12 servings.