Mix oats milk and granulated sugar and heat in a microwave oven at 600w for 1 minute.
Mix egg yolks and flour well.
Add 1 to 2 a little at a time and mix well
Heat 3 in a microwave oven at 600W for 1 minute at a time and mix with a whisk (repeat several times until creamy).
Put 4 and love into a baking dish, add blueberries and press them into the dish.
Sprinkle the casonade on top and bake at 200°C for5 minutes.