Recipe for BUTTERMILK RHUBARB SQUARES

These squares are my new favorite thing to bake, I might be slightly obsessed. The brown sugar and cardamom give the squares a caramel type of flavor. If you want, you can change the brown sugar to white sugar, and omit the cardamom. 
The recipe makes a roasting pan size of a tart that is cut into 24 squares.

Crumble Mix

• 8 dl all-purpose flour
• 1 dl sugar
• 2 dl brown sugar
• 2 tsp baking soda
• 2 tsp baking powder
• 2 tsp vanilla
• 1 tsp cardamom
• 250g butter melted 

The Crust

• 2/3 of the crumble mix
• 2 dl buttermilk
• 1 egg

The Filling

• 1 liter (~500g) thinly sliced rhubarb
• 400g thick, natural yogurt
• 2 dl brown sugar
• 2 eggs
• 3 tsp vanilla

The Top

• 1/3 of the crumble mix, as is

1. Put the oven to 175° C (350° F) 
2. Melt butter and let it cool for a while. 
3. Rinse the rhubarb stalks and chop them into thin slices. No need to peel the rhubarb.
4. Mix the dry ingredients of the crumble mixture with each other 
5. Slowly add the melted butter into the dry mix, blending the butter into the mix with fingers until crumbly 
6. Transfer one-third of the crumble mixture to another bowl.
7. Break the egg (of the crust) into a bowl and mix it with the buttermilk. 
8. Add the buttermilk and egg mixture to the 2/3 of crumble mix. Mix the dough with a fork.
9. Spread the dough on a baking sheet over a baking paper. 
10. Sprinkle the pieces of rhubarb on the surface.
11. Prepare the filling mix by cracking the eggs into a bowl, mixing them with a fork and add the thick yogurt, brown sugar and vanilla. 
12. Pour the yogurt and egg mixture over the rhubarb. 
13. Sprinkle the rest of the crumble mixture (1/3 that was separated at the beginning) on the surface.
14. Bake the pie on the medium level of a 175C oven for about 45 minutes. 
15. Allow the pie to cool before cutting.

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