Шаг 1
First, prepare the condensed milk: place the can in a pot, cover with cold water so it's fully submerged, and boil for 2 hours after water starts boiling.
Шаг 2
Put sour cream and salt in a bowl. Quench baking soda with vinegar and add. Add flour, ground cinnamon, and vanilla sugar, mix with a mixer. Add soft margarine and continue mixing.
Шаг 3
After thorough mixing, place the dough on a floured surface and knead, adding more flour. Divide into three parts and form balls. Place in freezer for 20 minutes.
Шаг 4
Roll out the dough into a 1–2 mm thick sheet, place it on a baking tray. Prick with a fork to prevent air bubbles. Preheat the oven to 175°C and bake for 20–25 minutes until light brown.
Шаг 5
Spread boiled condensed milk on each layer right after baking. Use about 1/3 can per layer. Repeat for all three. Trim the cake into a neat rectangle. Crush the trimmings into crumbs.
Шаг 6
Sprinkle crumbs on top and gently press with your hand. Refrigerate for 3–4 hours or overnight. Cut into slices and serve with tea. Enjoy!