Vanilla Napoleon Slice

Directions

1. 1
   Divide puff pastry into two parts and roll each out into a thin (2-3 mm - 1/8 in thick) square of 30 cm (about 11-12 in), use plain flour to prevent sticking, then trim irregularities
2. 2
   Transfer the pastry square using a roller onto buttered baking sheet of about 32 x 39 cm (about 13 x 16 in), cover with baking paper, put atop a smaller baking sheet to weigh the pastry otherwise it would swell, cool in the fridge for 30 min., or in freezer for 5 min.
3. 3
   Put in a preheated oven at 190 ° C (375° F) and bake for 10-13 min., take out from the oven, remove the baking and paper sheets, continue baking for about 5 min. until golden brown
4. 4
   Repeat with the second part of the pastry
5. 5
   Combine trims from the first and second part of pastry, roll out into the square, repeat as with previous pastries, in the end you should have 3 pastry sheets from which you need 18 nice squares of 9 cm (about 3 1/2 - 4 in)
6. 6
   Using a large serrated knife, cut into squares of 9 or 10 cm (about 3 1/2 - 4 in), handle carefully the pastry, place squares on each other
7. 7
   Mix egg yolks with sugar, starch, and flour
8. 8
   Slowly mix in hot milk and simmer over the low heat until thick, add flour if necessary
9. 9
   Stir in mascarpone (or butter) and vanilla, cover with a plastic wrap to prevent the skin formation, refrigerate for a few hours
10. 10
    Fill a confectionery bag with the custard and pipe 6-7 equally thick strips on a pastry square
11. 11
    Cover with another pastry square and repeat 4 more times
12. 12
    You should get 3 squares with five layers that are kept in the fridge, when served cut with a serrated knife into 4 smaller squares or 2 rectangles
13. 13
    Sprinkle with sugar