Stir the sugar, salt and the warm milk, and let stand for a few minutes until the sugar melt.

In a medium bowl, add flour and yeast, Beat in the egg and vanilla until well blended. stir into the sugar mixture, add oil and make a dough

Roll dough out on a floured surface to 1/3 inch thickness. Cut into doughnuts using a donut cutter. Let stand untill dough rise.

Heat the oil in a large deep skillet to 375 degrees F (190 degrees C). Fry doughnuts in the hot oil until golden, turning over once.