In a small bowl, mix yeast, 1 teaspoon sugar and 1/3 cup warm water. Let stand 15 minutes or until bubbly.
In a large bowl, beat eggs until thick. Beat in the yeast mixture, 2 tablespoons sugar, butters and salt.
Then add the 1/2 cup warm water and mix until fully incorporated. Add 2 cups flour and mix well. Add remaining flour and knead until dough is smooth.
Place dough in a greased bowl. Cover with greased plastic wrap and let rise 2 hours or until doubled. Punch down dough and let rise again until doubled (2 hours).
Knead by hand a few times and then turn out onto a lightly floured board. Divide the dough into three pieces (each one slighty smaller than the other) .
Divide each piece into three pieces and braid.
Make three round braided loaves to be stacked on top of each other.
Place the three loaves in 3 tube pans of decreasing size, 30 cm, 25 cm and 20 cm.
Cover with greased plastic wrap and let rise in a warm place until almost doubled (2 hours).
Heat oven to 180°. Bake 50-60 minutes. Brush bread with eggwash the last 5 minutes of baking.
Remove from oven and turn out of pans to cool completely on a wire rack.