Preheat the oven to 350°F (175°C) and grease a mini muffin pan.
In a mixing bowl, cream together the butter and sugar until light and fluffy.
Add eggs one at a time, beating well after each addition.
Mix in the sour cream, lemon juice, lemon zest, and vanilla extract.
In a separate bowl, whisk together the flour, baking powder, baking soda, and salt.
Gradually add the dry ingredients to the wet ingredients, mixing until just combined.
Spoon the batter into the prepared mini muffin pan, filling each cup about 3/4 full.
Bake for 12-15 minutes, or until a toothpick inserted comes out clean.
Allow cakes to cool slightly in the pan before transferring to a wire rack.
While cakes are cooling, whisk together powdered sugar and lemon juice to make the glaze.
Dip the tops of the cooled mini cakes into the glaze and let set before serving.