Directions

1. For filling, in a small saucepan combine dates, granulated sugar, and water. Bring to boiling; reduce heat. Cook and stir about 2 minutes or until thickened; cool.
2. In a large mixing bowl beat butter and shortening with an electric mixer on medium to high speed for 30 seconds. Add the brown sugar, baking soda, salt, and cream of tartar. Beat until combined, scraping sides of bowl occasionally. Beat in eggs, whipping cream, and vanilla until combined. Beat in as much of the flour as you can with the mixer. Stir in any remaining flour. Divide dough in half. Cover; chill dough 1 to 2 hours or until easy to handle.
3. Roll half the dough between pieces of waxed paper into a 13x8-inch rectangle. Spread with half of the filling. Sprinkle with half of the walnuts. Starting from a long side, roll up dough using bottom layer of waxed paper to help lift and guide the roll. Pinch dough edges to seal; wrap in plastic wrap. Repeat with remaining dough, filling, and walnuts. Freeze 2 to 24 hours.
4. Grease cookie sheets or line with parchment paper; set aside. Use a serrated knife to cut rolls into 1/4-inch-thick slices. Place slices 1 inch apart on prepared cookie sheets. Bake in a 375 degrees F oven for 8 to 10 minutes or until bottoms are light brown. Cool on cookie sheet 1 minute. Transfer to a wire rack; let cool. Makes about 60 cookies.