In a small bowl, combine the raisins and orange juice. Add enough hot water to fully cover the raisins. Set aside so the raisins can soak up the liquid for at least 30 minutes, or up to overnight.

In a large mixing bowl, whisk to combine the yeast mixture, eggs, orange zest, and softened butter.

Add the flour and salt, and mix with a large spoon until it forms a sticky dough, and there’s no dry flour visible. (The dough will be soft and sticky at this point.)

Lightly dust a clean work surface with flour, and knead the dough by hand for about 5 to 8 minutes, until the dough is smooth, soft, and springs back to its original shape when you indent it with your finger. Continue sprinkling a little flour on your counter as you knead the dough as needed, to prevent it from sticking to your counter.

Shape the dough into a ball. Place the dough ball back in the mixing bowl, and cover with a kitchen towel. Let it rest and rise in a warm place for about 2 hours, until it doubles in size.

In a medium saucepan on medium-high heat, bring the milk, sugar, and vanilla extract to a simmer, stirring frequently.

Grind the poppy seeds in a food processor or coffee grinder. Since the seeds are already so small, they might not change in appearance that much, but they should smell much more nutty.

Add the ground poppy seeds. Boil for one minute, stirring constantly.

Remove from the heat and add the butter. Stir occasionally until the butter is melted.

Set aside to cool for 5 to 10 minutes. Then crack in the egg and whisk to combine.

Drain the soaked raisins and stir them into the poppy seed filling. Set aside to cool and thicken.

Line a baking sheet with parchment paper.

Spread half of the cooled poppy seed filling over the rolled-out dough, leaving a 1-inch border around all four edges.

Starting from one of the longer sides, roll up the dough and the filling into a spiral log. Pinch the two short ends closed and tuck them underneath, to prevent the filling from spilling out.

Carefully transfer the roll to your prepared baking sheet, with the seams facing down. Repeat with the remaining half of dough and poppy seed filling.

Cover the baking dish with a kitchen towel, and allow the dough to proof for 30 minutes.

Preheat the oven to 350°F. In a small bowl, whisk the egg with a teaspoon of water or milk to make an egg wash.

Brush the tops of the strudels with the egg wash. Sprinkle the sliced almonds on top of the strudels.