1. In a blender combine the milk, eggs, and vanilla. Add the flour, sugar, salt, and cinnamon on top of the liquid ingredients. Cover and blend for 25 to 30 seconds or until just incorporated, stopping to scrape down sides as necessary.
2. Coat an 8-inch nonstick skillet with flared sides with nonstick cooking spray. Heat over medium heat. Pour about 1/4 cup of the batter in the hot skillet and swirl to make a thin even layer. Cook for 1 1/2 minutes or until bottom is lightly browned. (The wetness will dissipate and the crepe will resemble a very soft pancake.)
3. Fold the crepe in half, then fold in half again; transfer to a plate. Sprinkle generously with about 1 tablespoon powdered sugar; set aside. Repeat with remaining batter. Serve each crepe with a lemon quarter for squeezing (the lemon juice creates a lemony icing as it mixes with the powdered sugar).