Layered biscuits with sour milk

Ingredients:

• 2 cups of premium flour + extra for working with the dough
• 2 tsp baking powder
• 1/4 teaspoon of baking soda
• 1 teaspoon of sugar
• 1 teaspoon fine salt
• 7 tablespoons chilled unsalted butter, cut into slices
• 3/4 cup sour milk or kefir + extra for greasing the buns
• Special equipment: cookie cutter with a diameter of 6 cm.

Preparation:

1. Preheat oven to 220°C. Line a baking sheet with parchment paper.
2. In a medium bowl, whisk together the flour, baking powder, baking soda, sugar, and salt. Using your fingertips, rub 2 tablespoons of cold butter into the flour until completely absorbed. Rub the remaining 5 tablespoons of cold butter into the flour until pea-sized pieces remain. Using a silicone spatula, fold the buttermilk into the flour and knead into a rough dough.
3. Dust a cutting board or work surface with flour and turn the dough out onto it. Form the dough into a 1 cm thick rectangle. Fold the dough three times, like a letter, and then form it into a 2 cm thick rectangle.
4. Using a 6 cm cookie cutter, cut out buns and place them on the prepared baking sheet. Gather up the dough scraps and cut out more circles. Brush the surface of the dough with sour milk.
5. Bake until the tops are lightly browned, about 15 minutes. Cool the buns in the pan for at least 5 minutes. Serve warm or at room temperature.