Combine flour, sugar, yeast and salt in a medium-large bowl. Stir well to combine, then make a well in the center. Set aside.
Melt butter in the microwave for 30-50 seconds on high power, until just melted. Remove from the microwave and add the ¼ cup of milk. Stir with a fork then add the egg and egg yolk. Stir again until well mixed.
Add the milk mixture to the well in the center of the flour. Add the hot tap water to the well then stir to combine. Continue stirring until all flour is incorporated. Cover the dough with plastic wrap and set aside in a warm place to rise until double in size, about 1 hour.
Flatten one of the dough balls with the palm of your hand then push it out with your fingers to make a circle of dough approximately 2½ inches in diameter. Spread the circle with a scant ½ teaspoon of butter and fold it in half. Place the folded circle in one of the prepared pans with the open edges facing up. Repeat this sequence with the remaining portions of dough to fill up one of the prepared pans.
Towards the end of the rising time, preheat the oven to 375˚F and prepare the egg wash by vigorously whisking together the egg with 1 tablespoon of water.
When the oven has reached 375˚F, use a pastry brush to brush each loaf with the egg wash. Try to be careful not to let the wash drip down the sides of the loaves into the pan.
See Café Tips for more detailed instructions and tips.