Into a bowl, add the warm water, the yeast, the salt, the butter and the sugar, mix very well. Add the flour and mix until a dough is formed (it's supposed to be a sticky dough, so do not add more flour), cover the bowl with plastic wrap and let it rest for 40 minutes.
Put the dough on a floured surface, sprinkle some flour over the dough and cut it into 8 equal-sized pieces. Round these pieces into little balls. Place these dough balls one next to the other on a nonstick skillet and let them rest for another 35 minutes.
Turn on the heat and cook over very low heat for 10 minutes, flip the bread over a sheet of parchment paper, then put the bread back in the skillet (with the parchment paper under the bread). Cover the skillet and cook for another 10 minutes.
Remove from the skillet and add condensed milk to taste.