Add yeast and 2 teaspoons sugar to warm milk, and set aside until foamy
Add the eggs, sugar, butter, milk and vanilla extract to the bowl of a stand mixer or large mixing bowl, and mix until combined
Stir in the yeast mixture, salt and 2 cups flour
Gradually add 3 more cups flour, and knead with dough hook attachment or by hand until dough is smooth. Add another cup flour if necessary. Dough should be slightly sticky but shouldn't stick to your hands
Stir in the raisins until well blended
Place dough ball in a large mixing bowl, greased well with butter. Cover with aluminum foil or plastic wrap and place in a warm place to rise for 1 hour or until doubled
Punch dough down. Then, turn onto a lightly floured surface, and cut off slightly less than ¼ of the dough
Divide small piece of dough into 3 pieces, and roll out into 3 long ropes, using your fingers
Pinch ends of ropes together, and braid into 1 long braided rope. Cut rope in half
Place larger piece of dough into buttered 9-inch cake pan, and smooth out so it evenly covers the pan
Form a cross with the braided dough on top of the paska
Place dough in a warm place and let dough rise for 30 to 45 minutes. Dough should be close to top of cake pan
Preheat oven to 350℉
Mix egg and water together. Gently brush the egg wash over the top of the bread
Place paska dough into preheated oven, and bake for 40-45 minutes or until golden brown. Bread should sound hollow when tapped, and temperature should be 190℉ according to instant read thermometer. It may take up to 50 minutes.
Remove bread from oven, and allow to cool slightly. Gently remove from cake pan, and allow to finish cooling on a wire baking rack