Combine 2 ½ cups all purpose flour, 1 ½ teaspoons instant yeast, 2 Tablespoons granulated sugar, and ½ teaspoon salt in a large bowl.
Pour in ½ cup lukewarm milk (not hot!) and 1 Tablespoon warm water, crack in 1 egg, and add pieces of softened ½ stick unsalted butter.
Process the mixture into a smooth, soft dough. Start by roughly mixing the ingredients in the bowl with a wooden spoon. Then, turn the mixture onto a floured surface, keeping a small handful of flour nearby. Begin kneading the dough with your hands, and if it sticks, dip it into the prepared flour. Continue kneading until the dough is no longer sticky and becomes beautifully elastic.
Return the smooth ball of dough to the bowl and cover it with plastic wrap. Place the bowl of dough in a warm spot to rise for an hour until the volume doubles. Halfway through the rising time, knead the dough briefly to support further leavening.
Prepare the pan in which you will bake the paska bread. I used a small 8-inch springform pan. Lightly grease the pan with butter and line the bottom and sides with baking paper. The butter helps the paper stick to the sides of the pan and hold nicely.
From the risen bread dough, separate a portion about the size of an egg. Divide this dough into four pieces and roll each piece into a thin strand. Twist two strands together to make a simple braid, and repeat with the remaining two strands.
Shape the remaining dough into a loaf and place it, seam side down, in the lined pan. Arrange the prepared braids over the loaf in the shape of a cross, tucking their ends slightly between the loaf and the sides of the pan.
Cover the prepared paska bread with a clean kitchen towel and let it rise for another 30 minutes.
Make an egg wash by whisking ½ egg with a fork. Brush the entire surface of the bread, including the braids, with the egg wash.
Preheat the oven to
370 °F. Transfer the Paska bread to a center wire rack, close the oven door, and bake for about 25-30 minutes, depending on its size.