Add egg yolks, both vinegars, water, salt, mustard powder, and paprika to a tall narrow jar
Pour all the oil on top without stirring
Let the yolks settle to the bottom
Place immersion blender flat on the bottom of the jar
Turn it on high and hold completely still for 15 to 20 seconds until the bottom half turns thick and white
Slowly pull the blender upward through the rest of the oil for about 10 to 15 seconds
Blend up and down for 5 more seconds to finish
Chill at least 1 hour before tasting
