Whisk together the flour, sugar, baking powder and salt in a medium bowl until combined. Set aside.
In another bowl, whisk together milk, eggs and vanilla until combined.
Gently add dry ingredients to the milk/egg/vanilla mixture and whisk until the batter is smooth.
Add vegetable oil to a medium size saucepan until it is about 2-3" deep. Heat over medium heat until the oil is about370-375F. You can check the temperature with a candy thermometer.
When oil reaches the right temp, drizzle about 1/2 cup of funnel cake batter into hot oil. Make sure to drizzle in a thin stream and criss cross and swirl the batter over itself. You don't want any portion of the batter to be much thicker than another portion. It's all about an even drizzle.
Fry each side of the funnel cake for about 90 seconds each (per side) and then remove from oil and place on a paper towel lined plate.
Sprinkle powdered sugar on the funnel cake and serve warm.
Repeat the process with remaining batter.
Notes
Add additional milk to the batter if it is too thick to properly drizzle.You don't have to use a funnel to make funnel cakes. You can drizzle from a measuring cup, use a pastry bag or a toddler silicone food pouch with a spout.