Blueberry pie with meringue

This is one of my favourite cakes. Easy, fast and gorgeous looking. Got it from my subscription to CookingPalette.
All the times I have done it was with gluten free flour. Some of you know it is pretty tricky to deal with, but buttery pastry is bearable.

Ingredients:
batter

• 4 yolks
• 4 tbsp milk
• 0.5 cup of sugar (~120 ml)
• 150 g butter
• 2.5 cup flour
• 1 tsp baking powder

filling

• 2.5 cup blueberries (any other Nordic berries will work as well)
• 0.5 cup sugar

top

• 2-4 egg whites (depends how thick meringue you want)
• up to 0.5 cup sugar

Procedure: 

1. Pre-heat oven for 180 C and butter the traybake.
2. Mix all the ingredients for batter together, if you have a food processor - you may use it. The batter will look crumbly.
3. Take two sheets of baking paper and roll a thin layer out of made pastry. It will keep your table cleaner and easier to get it non-sticky.
4. Place in a traybake, cut the extra edges and prick the bottom using a fork. Bake for 20-25 minutes.
5. Take pre-baked bottom out and cool for a few minutes, the pastry will go down.
6. Mix berries and sugar.
7. Beat egg whites to high peaks. Add sugar and beat a little more until it is homogeneous. If you can turn a bowl upside down without moving the mixture - it is ready. For easier beating, make sure eggs are fresh and cooled.
8. Place a filling and then meringue. Try to make a small peaks for a nicer look. Bake for 20 minutes.
9. Cool down before serving.

Estimated preparation time: 20 min

Estimated cooking time: 50 min

Notes: frozen berries will make a pastry more moisture, giving to the cake a smoother taste.