Preheat the oven to 350°F (175°C). Grease a 9-inch pie dish with cooking spray or butter.
In a large bowl, combine the blueberries, granulated sugar, lemon juice, and vanilla extract. Gently toss to coat the blueberries and set aside.
In another bowl, whisk together the eggs and milk until well combined.
Add the flour, baking powder, and salt to the egg mixture, whisking until smooth.
Pour the egg mixture over the blueberries in the bowl and gently fold to combine.
Pour the mixture into the prepared pie dish, spreading it evenly.
Bake in the preheated oven for 35-40 minutes, or until the pie is set and lightly golden on top.
Remove from the oven and let cool for at least 15 minutes before slicing. Dust with powdered sugar if desired.