Preheat oven to 350 degrees. Grease a muffin tin and place on aluminum lined baking sheet.
Divide croissant cubes among muffin cups.
Press blueberries on top of croissant cubes.
In a standing mixer, beat cream cheese by itself until fluffy.
Add in the milk, egg, vanilla extract, and lemon juice and beat together until smooth. Scrap down the sides as needed. Pour mixture evenly over muffin cups.
Bake for 30-40 minutes or until set and browned. Let cool in muffin tin for a few minutes before removing. Transfer to wire rack and cool completely or until desired temperature. (I like to serve mine warm).