Preheat oven to 350 degrees F (175 degrees C). Grease a 9-inch springform pan.
In a medium bowl, whisk together the flour, baking powder, baking soda, and salt. Set aside.
In a large bowl, cream together the butter and sugar-free sweetener with an electric mixer until light and fluffy. Beat in the eggs, one at a time, then stir in the vanilla extract and yogurt.
Gradually add the dry ingredients to the wet ingredients and mix until just combined.
Gently fold in the blueberries and walnuts. Pour the batter into the prepared pan.
Bake for 40 to 45 minutes, or until a toothpick inserted into the center of the cake comes out clean.
Allow cake to cool completely before serving.
Interesting Facts
This cake is a great way to enjoy a sweet treat without all the added sugar.
Blueberries are high in antioxidants and Vitamin C, making this a healthy option.
You can also substitute other berries or nuts in this recipe.