2 1/2 cups of all purpose flour
1 1/2 teaspoons baking powder
1/2 teaspoon baking soda
3/4 cup white sugar
1/4 teaspoon salt
2 eggs beaten well
1 cup buttermilk
1/4 cup lemon juice
2 tablespoons lemon zest
1/2 cup melted butter
1 teaspoon vanilla
2 cups blueberries
Grease a 9×13 baking pan and set aside.
In a large mixing bowl, whisk together the flour, baking powder, baking soda,sugar and salt.
Add in the eggs, buttermilk, lemon juice, lemon zest, butter and vanilla.
Beat with a mixer until blended.
Fold in the blueberries gently.
Spoon the dough into the prepared baking pan. Cover with plastic wrap and refrigerate overnight.
In the morning, remove the pan and place on the counter while the oven is warming. Pre-heat your oven to 350 °F.
Bake in the oven for 25-35 minutes, or until a cake tester inserted comes out clean.
Remove and serve while warm!