In a stand mixer, combine 1 cup of warm whole milk, 2 teaspoons of dry active yeast, ¼ cup of granulated sugar, and 4 tablespoons of melted Kerrygold salted butter. Whisk until well blended, then let the mixture rest for about 5 minutes.

Once the yeast mixture is bubbly, add 4 cups of unbleached all-purpose flour and 1 teaspoon of kosher salt. Knead on medium-low speed for about 12 to 15 minutes until smooth and elastic.

Transfer the kneaded dough into a lightly oiled bowl, cover, and let it rise in a warm place for about 1 hour until doubled in size.

In a medium bowl, mix together 8 ounces of cream cheese, ½ cup of full-fat sour cream, 1 teaspoon of pure vanilla extract, ½ cup of powdered sugar, and the zest of 1 lemon. Blend until smooth.

Turn the risen dough onto a floured surface, punch it down to release air, and divide into equal portions. Shape into smooth balls.

Create indentations in the center of each dough ball, pipe the cream filling into each, add blueberry preserves and a few fresh blueberries on top.

Cover the filled buns and let rise for another 30 minutes. Preheat the oven to 350°F (175°C) during this time.

Brush the edges of each bun with a beaten egg before baking for a golden glaze. Bake for 25 minutes until golden brown.

Let cool slightly, then dust with powdered sugar before serving.