Preheat the oven to 325°F (165°C). Thoroughly grease a 10-inch Bundt pan to prevent sticking.

In a large mixing bowl, combine the yellow cake mix and the instant lemon pudding mix. Create a well in the center of the dry ingredients and add the orange juice, vegetable oil, eggs, and lemon extract. Using an electric mixer, beat the mixture on low speed until just combined. Increase the speed to medium and continue beating for approximately 4 minutes, ensuring the batter is smooth and uniform.

Pour the batter evenly into the prepared Bundt pan. Bake in the preheated oven for 50 to 60 minutes, or until a toothpick inserted into the center of the cake comes out clean. Allow the cake to cool in the pan for 10 minutes before carefully inverting it onto a wire rack. Let it cool completely for an additional 20 minutes.

In a small saucepan over medium heat, combine the granulated sugar, orange juice, and unsalted butter. Stir continuously and cook for approximately 2 minutes, or until the mixture is smooth and slightly thickened.

Transfer the cooled cake to a serving platter. Evenly drizzle the prepared glaze over the cake, allowing it to soak in for optimal flavor and moisture.