Preheat oven to 325°F. Grease and flour a 10” tube pan or a 12-cup Bundt pan.
In a bowl, whisk together sour cream, eggs, and vanilla extract.
In a bowl, combine flour, Splenda Sugar Blend, and baking soda. Use a fork or pastry blender (or an electric mixer on lowest speed) to cut butter into dry ingredients until crumbly.
Add about ¼ of the sour cream mixture; mix on low speed to combine, then on medium speed for 30 seconds or until batter is smooth. Repeat 3 times with remaining sour cream mixture.
Spoon batter into prepared pan.
Bake for 1 hour and 20 minutes or until a wooden pick inserted in center comes out clean. Cool cake in pan for 10 minutes, then remove from pan and cool completely on a wire rack.