In a blender, blend milk, eggs, butter, sugar, vanilla, salt, flour, and cocoa powder 15 to 20 seconds, or until batter is smooth. Chill at least 30 minutes, or overnight.
Spray nonstick cooking spray onto an 8-inch frying pan. Pour about 1/4 cup batter into the pan and cook over medium-low heat. Turn pan immediately from side to side to form an even circle. Cook 1 to 2 minutes per side, or until lightly browned. Remove from heat and stack on a plate.
Serve with your favorite toppings.
Notes
Make-ahead: The batter can be made up to 24 hours in advance and stored in the refrigerator until ready to cook. The crepes can be made up to 3 days in advance. Storage: Add to a zip-top bag or covered container and layer parchment in between each crepe. Place in fridge for up to 3 days place in the freezer for up to 3 months.Reheating: Heat in microwave or on the skillet over low heat until warm. You can also place on a baking sheet in the oven at 175°F for 5 minutes, or until warm.