Preheat your oven to 350°F (175°C). Grease and flour a 10-cup pan.

In a large bowl, mix flour, sugar, baking powder, baking soda and salt until combined.

Add the softened butter to the dry ingredients and mix with a hand mixer or stand mixer until the mixture resembles coarse crumbs.

In a separate bowl, beat the eggs lightly. Add the yogurt (or sour cream) and vanilla extract, and mix until smooth.

Gradually add the wet ingredients to the dry ingredients, mixing until everything is well combined. Be careful not to overmix.

Gently fold in the blueberries using a spatula until evenly distributed throughout the batter.

Pour the dough into the prepared pan and distribute it evenly.

Bake in the preheated oven for 40 to 50 minutes or until a toothpick inserted into the center of the cake comes out clean.

Let the cake cool in the pan for about 10 minutes, then carefully invert the cake onto a wire rack to cool completely.

Slice, serve, and enjoy your delicious Blueberry Breakfast Cake!