Day 1: Making the Cronut Dough

1. In a large mixing bowl or the bowl of a stand mixer, combine bread flour, all-purpose flour, sugar, salt, and yeast. Make sure the salt does not come into direct contact with the yeast.
2. Gradually stream in water or milk while mixing on low speed until the dough starts coming together.
3. Add the softened butter cubes one at a time while mixing. Continue kneading for 5-10 minutes until the dough pulls away cleanly from the sides of the bowl.
4. Perform a gluten window check by stretching a small piece of dough. It should stretch thinly without tearing.
5. Shape the dough into a tight ball and transfer it to a lightly oiled bowl. Cover with plastic wrap and let rise in a warm place for about 90 minutes or until doubled in size.
6. Once risen, turn the dough onto a work surface, press it into an oval shape, and fold the top and bottom edges into the center. Roll into a log, then flatten slightly.
7. Wrap in plastic and refrigerate for at least an hour or overnight.

Day 2: Laminating the Dough and Preparing the Fillings

Laminating the Dough (Butter Layers)

1. Roll out the chilled dough into a 7 x 22-inch rectangle. Spread the softened butter evenly over the surface.
2. Fold the dough into thirds like a letter and seal the edges to prevent butter from escaping. Refrigerate for 30 minutes.
3. Remove from the fridge, turn the dough 90 degrees, and roll it out to the same dimensions. Fold into thirds again and refrigerate. Repeat this process two more times for a total of three single folds.
4. After the final fold, cover the dough and refrigerate overnight.

Making the Strawberry Jam

1. Combine sliced strawberries and sugar in a saucepan. Let sit for 15 minutes to release juices.
2. Heat the mixture over medium-low, stirring occasionally, until it starts bubbling.
3. Mash the strawberries and continue cooking until thickened. Strain to remove seeds and refrigerate until needed.

Making the Vanilla Bean Pastry Cream

1. In a bowl, whisk together egg yolk, whole egg, sugar, flour, and cornstarch.
2. In a saucepan, bring milk and vanilla to a light boil, then remove from heat.
3. Slowly pour a small amount of hot milk into the egg mixture, whisking constantly to prevent curdling.
4. Pour the tempered mixture back into the saucepan and cook over medium-low heat, whisking continuously until thickened.
5. Transfer to a bowl, cover with plastic wrap touching the surface, and refrigerate until ready to use.

Day 3: Cutting, Proofing, Frying, and Filling

Cutting the Cronuts

1. Roll out the chilled dough to 16 x 8.5 inches and 0.5 inches thick.
2. Use a 3.5-inch round cutter to cut out 8 circles. Cut a hole in the center of each with a 1.2-inch cutter.
3. Arrange on a lined tray, cover loosely with plastic wrap, and let proof for 90 minutes until they puff up.
4. Refrigerate for 30 minutes before frying for easier handling.

Making the Strawberry Sugar

1. Combine crushed freeze-dried strawberries with granulated sugar in a bowl.

Frying the Cronuts

1. Heat 2 liters of frying oil in a pot to 375°F (190°C).
2. Fry a few cronuts at a time, flipping occasionally until golden brown.
3. Remove with a slotted spoon and drain on paper towels.

Filling the Cronuts

1. Once slightly cooled, roll the cronuts in strawberry sugar.
2. Whip the chilled vanilla bean pastry cream until smooth and transfer to a piping bag.
3. Pipe the cream into four points of each cronut, filling halfway.
4. Fill the remaining space with strawberry jam.
5. Garnish with extra pastry cream and fresh strawberry slices.