Preheat the oven to 350°F (175°C).

Lightly grease a 10-inch tube pan and set it aside.

In a large mixing bowl, whisk together the flour, baking powder, sugar, and salt.

In another bowl, mix the egg yolks, vegetable oil, water, and vanilla extract until well combined.

Gradually pour the wet mixture into the dry ingredients. Stir until just combined, then gently fold in the blueberries.

In a clean bowl, beat the egg whites and cream of tartar until stiff peaks form.

Gently fold the egg whites into the batter until no streaks remain.

Pour the batter into the prepared pan.

Bake for 50-60 minutes or until a toothpick comes out clean.

Once baked, turn the pan upside down to cool completely before removing it.

Dust with powdered sugar or top with whipped cream before serving.