Preheat your oven to 350°F (175°C).
Lightly grease and line a round cake tin with parchment paper.
In a bowl, mix the 2 3/4 cups of flour, 2 teaspoons of baking powder, 1/2 teaspoon of baking soda, and 1/4 teaspoon of salt.
Set aside.
In a separate large bowl, beat the 1 cup of sugar with 1/2 cup of vegetable oil.
Add the eggs one at a time, beating well after each addition.
Add the zest of 1 lemon, then the juice.
Mix well to combine.
Gradually add the dry ingredients to the wet mixture, alternating with 1 cup of milk.
Begin and end with the dry mixture.
In a medium bowl, toss the 1 cup of blueberries with 1 tablespoon of cornstarch until well-coated.
Gently fold the blueberries into the batter.
Pour the batter into the prepared cake tin.
Smooth the top with a spatula for even baking.
Bake for 50-55 minutes or until a toothpick inserted into the middle comes out clean.
Let the cake cool in the tin for about 10 minutes before transferring it to a wire rack to cool completely.