Preheat oven to 325°F (165°C). Do not grease the tube pan.

Sift together cake flour, 1 cup sugar, baking powder, and salt in a large bowl.

In a separate bowl, whisk together oil, egg yolks, water, vanilla extract, and lemon zest.

Pour wet ingredients into dry ingredients and whisk until smooth.

In a clean, dry bowl, beat egg whites until foamy. Add cream of tartar and continue beating.

Gradually add the remaining ½ cup sugar while beating egg whites until stiff peaks form.

Gently fold one-third of the egg whites into the batter to lighten it.

Fold in remaining egg whites in two additions until just incorporated.

Toss blueberries with 1 tablespoon of flour and gently fold into the batter.

Pour batter into ungreased tube pan and run a knife through to remove air pockets.

Bake for 55-60 minutes until toothpick inserted comes out clean.

Immediately invert pan and cool completely (about 1½ hours).

Run a thin knife around edges to release cake from pan.

Prepare glaze by whisking powdered sugar, blueberry puree, lemon juice, and vanilla.

Drizzle glaze over cooled cake and garnish with fresh blueberries if desired.