250 g butter
25 g fresh yeast
250 ml milk
1 tbsp sugar
1 tsp salt
about 900 ml flour
1 egg for glazing
All the ingredients must be chilled before baking, so start the preparations on the previous day of baking by placing the flour in freezer and the eggs, milk, sugar, salt and yeast in refrigerator. Soften the butter with your hands and roll it out into a 25 × 25 cm square between two parchment papers. Wrap the papers' sides around the butter and place it also in refrigerator overnight.
On the next day, dissolve the yeast in the cold milk. Add the eggs, sugar, salt and finally 800 millilitres of flour. Knead the dough until it is smooth, shiny and elastic. Add more flour if the dough seems very runny and sticky. The kneading is most easily done with a heavy-duty tabletop mixer fitted with a dough hook.
When the dough starts coming away from the side of the mixing bowl and forms a ball around the hook, remove it from the bowl and knead it on a floured surface. Roll the dough into a rectangle sized 45 × 30 cm. Take the butter square out of refrigerator and strip the top parchment paper off its surface. Place the square butter-side down on the dough rectangle, covering 2/3 of it, then strip off the other paper as well (see figure 1). Work very quickly, so that the ingredients will not get too warm and thereby difficult to handle.
Fold the sides of the dough on the butter square. Then fold the dough into three parts by first folding the third with no butter on top of the buttered dough (see figure 2). Brush off any excess flour. Then fold the other half of the buttered dough on top of the rest of the dough (see figures 3 and 4).
Roll out the dough into a 1 cm thick rectangle and fold it again in three parts. Repeat the rolling and folding once more, wrap the dough in parchment paper and let it rest in refrigerator for 1 hour. Cut the dough in two parts and put the other part back in refrigerator. The dough is easier to handle in two parts.
Roll out the dough into a ½ cm thick circle, about 40 cm in diameter. Cut the disk into 8 - 10 wedges with a rolling cookie cutter or a sharp knife a pizza wheel works best here and roll each wedge into a croissant shape, starting with the wider end. Repeat all this with the other part of the dough.
Place the croissants on a baking sheet covered with parchment paper, cover with a towel and let rise for 1 - 2 hours in cool room temperature.
Glaze the croissants with a lightly beaten egg and bake at 225 °C for 9 - 15 minutes. Place the croissants on a wire rack to cool and serve them warm with butter, jam, honey or whatever you like.
Home-baked croissants made with real butter are flaky but soft, and not oozing with grease like those made commercially.
Although best eaten when newly baked, these croissants are also suitable for freezing. To defrost, warm the frozen croissants in cool oven (under 100 °C) in a heatproof, tightly closed plastic bag.
Recipe source: adapted from "Wienerleivät", Ihatsu, A. et al., ed. (1993) Otavan suuri keittokirja. Keuruu: Otava.