Easter surprise inside cookies

Directions

1. Start by preparing the the cookie dough. Whisk butter and sugar until creamy.
2. With a sharp knife, slit the vanilla pod lengthways. Scrape the seeds, and then stir in vanilla seeds, salt, and egg, until combined.
3. Fold in flour and mix. Divide the dough in 3. Reserve one portion inside a plastic bag. Then take the two remainig portions, and divide each in 3 (you should have 6 portions in total). Colour each portion using a pinch of gel edible colouring (blue, purple, green, yellow, orange and red), and roll out each portion between two sheets of parchment paper, forming a rectangle. The thickness should be adjusted depending on the size of your cookie cutter. Mine was 3.6 cm, so each layer was rolled out to a thickness of 0.6 cm. If the dough is too sticky, chill in the refrigerator for 30 minutes before rolling, covered with plastic wrap.
4. Pile up six rainbow sheets brushing egg white between the sheets. And let set in the freezer for 1 hour.
5. Slice the rainbow sheet with a knife. The width should be slightly smaller than the height of your cookie cutter. And then cut eggs using the cookie cutter. Pile up the rainbow eggs applying egg white as a glue between them, and freeze for 1 hour.
6. Then roll out the white dough we had reserved before, and cover the egg pile. Roll to form a cylinder, and freeze for 30 minutes.
7. Brush the roll with egg white, and roll in a bed of rainbow non pareils. Freeze again for 30 minutes
8. Slice the dough, and freeze again, whilst preheating the oven to 160 º C (320º F)
9. Bake using a double baking sheet for 15-20 minutes
10. Leet cool on a wire rack, and store in an airtight container