Wash and take away the stones from the mirabelles. Butter an oven form. Place the plums in the form.
Start the oven at 200 degrees Celsius.
In a casserole heat up the milk and the butter to finger warm temperature.
Mix the flour, corn flour, sugar and eggs in a bowl. Stir and add the milk bit by bit so you get a smooth paste.
Pour the batter over the mirabelles.
Place the pie in the middle of the oven for 10 minutes. Lower the heat to 180 degrees Celsius and let it bake for another 30 minutes.
Take out the pie and let it cool down. Place in the fridge for a few hours before serving.