You can make the filling up to 2 days in advance. Cover and refrigerate it until you’re ready to use it. If chilled, let it warm to almost room temperature to make it easier to scoop.

Immerse the raisins in boiling water until just covered, then let stand until they are plump and just a little warm.

Drain the raisins and put them into a cooking pot with all the other filling ingredients EXCEPT the chopped nuts.

Bring to a boil over medium heat, then cover and reduce heat to low. Allow to simmer for 30 minutes. Stir every few minutes to avoid scorching. The mixture will be thick and jammy.

Stir in the chopped nuts. Cover the bowl and refrigerate until needed.

Make the Dough. Combine the dry ingredients in the bowl of a large food processor (I use one with a 12-cup capacity). Pulse to combine.

Add the cold butter to the dry ingredients and pulse the food processor 8 to 12 times until incorporated. The mixture will look fairly sandy, but you’ll be able to see some clumps of butter.

In a separate bowl, whisk eggs, milk, and vanilla until smooth. Slowly add to the dry mixture and pulse until the dough comes together. Avoid overmixing.

Dump the dough into a bowl and gently pat together into a ball. Cut in half, gently flatten into a disk, and wrap each portion in plastic wrap. Refrigerate at least 30 minutes. Overnight chilling is recommended.

Preheat oven to 400°F (204°C). Work with one portion of dough at a time. Divide this portion in half and place the other half back in the fridge. Keeping the dough as chilled as possible will make it a little easier to work with. Form walnut-sized balls of dough (23 g or 3/4 oz). Place these balls back in the fridge to chill as you work through the remainder of the dough. You should end up with about 60 balls total.

On a flour-dusted surface, roll each ball out into a circle 4 inches (10.2 cm) in diameter. Work with only a portion of the balls at a time, and keep the remainder chilling in the fridge. The dough will be sticky, so keeping the dough chilled and using well- floured wax paper or parchment paper and a flour-dusted rolling pin will help here.

Add about 1 Tablespoon of filling to each circle, then brush an egg wash onto the outer edge of the lower half of the circle to help seal.

Fold the dough over to form a half circle, then gently press down on the filling so that it’s a little flatter. Press the edge with a fork to create a good seal. The cookies will look like pierogis.

Place on cookie sheets lined with parchment paper and brush the top of each cookie with egg wash.

Bake in the preheated oven for 9 to 12 minutes until lightly browned. Rotate the cookie sheets halfway through the baking time.

Let the cookies cool on baking sheet for about 3 - 4 minutes, then transfer to a wire rack to finish cooling.

For the icing: cream the butter, then add the powdered sugar. Whisk in the milk and vanilla until a slightly runny icing forms.

Spread the icing onto each cookie, then top with rainbow non-pareils, if desired. You can also top with colored sanding sugar.

For maximum freshness, store the cookies in a sealed container between layers of wax paper or parchment paper. They will keep at room temperature for up to a week.

Notes: 👉🏻 You can make these cookies smaller if you prefer. Adjust the baking time so they don’t overbake. 👉🏻If you don’t have a food processor, a large bowl will work. Use a pastry cutter to work the butter into the dough, then mix in the wet ingredients with a sturdy spoon. 👉🏻 The dough can be frozen. Thaw in the fridge before use. 👉🏻Amounts listed for the icing are somewhat approximate. Adjust to your liking. You can use almond extract instead of vanilla if you prefer.