Combine first 4 ingredients in a medium bowl; firmly press crumb mixture evenly into bottom and up sides of a lightly greased 9-inch springform pan. Bake at 350° for 10 minutes. Remove from oven; set aside.
Beat cream cheese at high speed with an electric mixer until creamy; gradually add 3/4 cup sugar and flour, mixing well. Add eggs, 1 at a time, beating after each addition. Stir in melted chocolate and almond extract; beat until well blended. Stir in sour cream, blending well. Pour into prepared crust.
Bake at 350° for 15 minutes. Reduce temperature to 225°; bake 1 hour or until cheesecake is almost set. Turn oven off, and partially open door; leave cake in oven 1 hour. Remove from oven; cool to room temperature on a wire rack. Cover and chill at least 8 hours. Run a knife around edge of pan, and release sides.
Place chocolate morsels and shortening in top of a double boiler; place over simmering water, and cook until chocolate melts, stirring often. Spoon glaze over cheesecake. Garnish, if desired. Store in refrigerator.