Combine lukewarm water and yeast in a stand mixer or large bowl. Let the mixture work for 5 minutes or until the yeast dissolves and it looks a little frothy.
Lightly whisk the evaporated milk, sugar, salt, egg, and vanilla extract. Then add it to the yeast mixture.
Add about 2 cups of flour and mix with a hand or dough mixer. If using a stand mixer, mix for 1-2 minutes.
Finally, add melted butter and mix until the dough is sticky but smooth. Add in additional flour to make a soft dough.
Turn the dough onto a lightly floured surface and knead for 1-2 minutes. Then place the dough in a greased bowl, turning once to coat it. Cover loosely with a clean cloth and let rise in a warm, draft-free place for a couple of hours or until doubled in size.
Punch the dough down and remove it from the bowl.
Divide the dough into four pieces for easy handling.
Roll your dough out onto a lightly floured surface to form a 10"x4" rectangle.
Cut the dough into ten squares (2"x2") using a sharp knife or pizza cutter.
Add a tablespoon of firm chocolate filling to one square and then cover it with another square. Crimp the edges by pinching them together tightly, so the beignets don't burst while frying.
Let the beignets rest for about 10 minutes before frying.
Working in batches to not crowd the pan, fry the dough squares until puffy and golden brown.
Remove them from the oil and place them on a paper towel to soak up extra oil.
Dust with powdered sugar immediately. Serve hot with café au lait, and enjoy!!!