Preheat the oven to 350 degrees F (175 degrees C). Grease and flour a 10-inch Bundt pan.

Beat sugar and butter together in a large bowl with an electric mixer until light in color and fluffy, about 5 to 7 minutes. Beat in eggs, one at a time, then stir in lemon extract.

Combine flour, baking powder, and lemon zest; gradually stir into cake batter alternating with milk. I like to use a spatula and stir by hand, mixing just until blended so the batter is not over mixed, scraping the bottom and sides of the bowl often. Gently fold in blueberries; spoon batter into the prepared pan.

Bake in the preheated oven until a toothpick inserted into the center comes out clean, about 1 hour to 1 hour 20 minutes. Let cool in the pan for at least 10 minutes, then invert onto a wire rack to cool completely.