Combine warm water, yeast and 1 teaspoon of sugar in the bowl of a stand mixer fitted with a dough hook¹. Stir and let sit for 5 minutes or until foamy.
Add melted butter and stir until combined.
In a separate bowl, stir together remaining 4 Tablespoons sugar, flour, and salt.
Turn mixer to low speed and gradually add flour mixture until combined. Dough should be soft and slightly tacky to the touch. If needed, add additional flour one Tablespoon at a time until desired consistency is reached. Continue to knead dough with dough hook (or transfer to a clean surface and knead by hand) until dough is elastic and smooth and pulls away from the sides of the bowl.
Transfer to a lightly oiled large bowl. Roll the surface of the dough through the oil, cover with a clean towel, and allow to rise in a warm, draft-free place until doubled in size (about 1-2 hours).
Gently deflate the dough and divide into 6 even pieces and roll each into a ball.
Line a baking sheet with parchment paper and sprinkle liberally with cornmeal.
Transfer dough balls to baking sheet, spacing several inches apart. Use a sharp knife to make an “X” on the top center of each dough ball. Prepare your egg wash by whisking together egg and 1 teaspoon water. Brush bread bowls generously with egg wash (don't discard this, you'll need it again a bit later on).
Cover with a clean towel and allow to rise while you preheat your oven to 425F (220C).
Once oven is preheated, bread bowls should have almost doubled in size.
Transfer risen bread bowls to 425F (220C) oven and bake for 15 minutes. Remove from oven and brush once more with egg wash. Return to oven and bake another 15 minutes or until golden brown and bread bowls sound hollow when tapped.
Allow to cool completely.
Once cooled, use a serrated knife to slice off the top of each bread bowl. Use a knife or just your fingers to hollow out the center of each bread bowl, then use as desired!