Prepare Yeast:
In a small bowl, combine warm milk, 1 tsp sugar, and yeast. Let sit for 5–10 minutes until foamy.
Mix Dough:
In a large mixing bowl, combine sugar, butter, eggs, salt, vanilla extract, and lemon zest. Add yeast mixture and stir to combine. Gradually add flour until a soft dough forms. Mix in raisins or candied fruit if using.
Knead Dough:
Knead on a floured surface for 8–10 minutes until smooth and elastic. Place in a greased bowl, cover, and let rise in a warm place for 1–2 hours, until doubled in size.
Shape Bread:
Punch down dough. Shape into a round loaf or place in a greased 9-inch springform or loaf pan. Add dough decorations if desired.
Second Rise:
Cover shaped dough and let rise for 30–45 minutes until puffy.
Prepare Egg Wash:
Preheat oven to 350°F (175°C). Mix beaten egg and milk. Brush gently over the top of the dough.
Bake:
Bake for 30–40 minutes, until golden brown and a skewer inserted in the center comes out clean. Cover loosely with foil if browning too quickly.
Cool and Glaze:
Let Paska cool completely on a wire rack. Optionally drizzle with powdered sugar glaze or add decorations before serving.