Preheat oven to 350 degrees F (175 degrees C). Prepare an 8-inch cake pan with cooking spray.
Whisk together the yogurt, eggs, canola oil, lemon juice, lemon zest, sugar, and 4 tablespoons limoncello in a large bowl. In a separate large bowl, mix the flour, baking powder, baking soda, and salt. Gently stir the dry ingredients into the wet. Do not over mix or the cake will be tough. Pour batter into prepared pan.
Bake in the preheated oven until top is golden and a toothpick inserted in the center of the cake comes out clean, about 35 minutes. Remove from oven and allow to cool slightly.
Stir the powdered sugar and 3 tablespoons of limoncello together in a small bowl until smooth. Poke small holes all over the top of the still-warm cake with a fork or toothpick. Spoon the glaze over the cake and spread with the back of a spoon. The glaze will seep into the cake and add moisture.