In a medium pot with a heavy bottom, heat the canola oil to 360 degrees F. Meanwhile, sift an even layer of flour on a flat surface. Flour a rolling pin. Roll the dough until it is very thin (about 1/8-inch thick). Cut the dough into fourths and work in small batches. Use any glass or small bowl that has a 3-to-4-inch diameter. Cut rounds, tracing around each one to assure the dough has been fully cut. You should have about 24 circles. Wrap each circle around a cannoli mold. Use a little of the egg wash on the edge of each round to seal it shut and to assure it won’t slide or fall off the mold before pressing it closed over the mold. Flare the edges out slightly from the mold. Flaring will allow the oil to penetrate each cannoli shell as they fry. Use a pair of tongs to hold the edge of the mold as you submerge and fry the shell in the oil until crispy, 2 to 3 minutes. Remove from the oil, and holding the mold in one had with your tongs, gently grip the shell in your other hand with a kitchen towel and carefully slide it off the mold. Set aside to cool. Repeat with all of the circles.