Summarize this article:

Place 1 tbsp (9.45 g) of yeast, 1 cup (240 ml) of lukewarm water, and 1 tbsp (12.5 g) of sugar into the bowl. Use a whisk to mix the ingredients together. Whisk the ingredients until the yeast and sugar have dissolved. Place 1 cup (120 g) of flour into the bowl with the yeast, lukewarm water, and sugar. Use a whisk to combine the flour with the other ingredients. Leave the mixture resting until small bubbles appear. The amount of time that it takes for the yeast to start bubbling depends on the temperature of the environment. The cooler the environment is, the longer it will take. Transfer 1/3 cup (75 g) of butter, 1 tsp (5 g) of salt, and the remaining 2 1/2 cups (300 g) of flour into the bowl with the yeast mixture. Use your hands to knead the ingredients together. Stop kneading once the butter is evenly distributed throughout the mixture. Keep the ingredients in the bowl while you are kneading. Take the dough from the bowl and place it onto a clean work surface. Use a rolling pin to roll the dough out until it looks like a thin sheet and is approximately 1⁄5 in (0.51 cm) thick.  Sprinkle some flour over the work surface if the dough starts to stick. Avoid rolling the dough too thin, otherwise, it may begin to break. Crack 3 eggs into a bowl. Use a whisk to beat the eggs until the whites and the yolks have combined. Coat the dough thoroughly using a pastry brush to spread the egg mixture out.  If you don’t have a pastry brush, you can use the back of a spoon to spread the egg mixture out instead.  Coating the dough with egg is called an egg wash. This helps to give the dough color and makes it shiny when it is cooked.

Summary:
Combine the yeast, lukewarm water, and sugar in a large bowl. Mix part of the flour into the bowl and let the mixture rest for 5-15 minutes. Knead the butter, salt, and remaining flour into the bowl. Roll the dough out on your work surface. Brush the dough with 3 beaten eggs.