Preheat oven to 350 degrees. Liberally coat with baking spray, or thoroughly grease and flour 12 mini-bundts, or pans for 24 cupcakes (or use paper liners if you like).
In a medium bowl, sift together the flour, baking soda, and salt. Set aside.
In another small bowl, stir together the yogurt and the milk just until smooth.
In a stand mixer, using the paddle attachment, cream together the butter, sugar, and lemon zest for about 5 minutes, until smooth and light. Stop to scrape the bowl periodically.
Add in the eggs one a time, still at medium speed, scraping down the bowl between each addition. Mix well after each egg.
On low speed, add in the flour mixture alternately with the yogurt in three additions. Mix just until incorporated. Increase the speed to medium and mix for 2 minutes more, until the entire mixture is smooth and light.
Add in 3 Tbsp. of the lemon juice and 1 Tbsp. of the limoncello. Blend just until evenly mixed, no more than 30 seconds.
Portion the batter evenly into your pan(s); smooth the top of the batter.
Bake until the center of each cake springs back when pressed lightly with a finger, and a toothpick inserted in the center emerges clean. This will be about 15 minutes for mini-bundts or cupcakes. Bake until the edges look golden brown. If you’ve made the cake in mini-bundt pans, let them cool for about 10 minutes before inverting the pan onto a cooling rack to remove the cakes. If you’ve baked cupcakes, let them cool no more than five minutes before removing them from their pans to a cooling rack..
To make the glaze, mix the confectioners’ sugar, 2 Tbsp. of lemon juice and 3 Tbsp. of limoncello in a small bowl and stir until any lumps are completely gone. If you’d like the glaze thicker, just stir in a bit more confectioners’ sugar until it’s the texture you prefer.
To apply the glaze, place the cooled cake(s) on a cooling rack set over a rimmed baking sheet. Using a spoon, drizzle the glaze liberally over each cake, allowing it to drip down the sides. Let the icing set for about 15 minutes before moving the cakes.