The wet ingredients need to be mixed well enough to break down the stringy portions of the egg so its protein is fully emulsified into the milk. It’s possible to do this by beating the ingredients with a fork, but it will take some time.
Quicker options include a milk frother or any blender. These take seconds to thoroughly blend the wet ingredients. My coffee/tea maker has a built in frother, but you can find a portable milk frother [Amazon affiliate link*] online.
When I use a blender, I prefer my Magic Bullet [Amazon affiliate link*]. It can handle a double recipe and is very easy to clean. It’s also a good option for chopping dried lemon and orange zest.
*Seasons of Scones is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sties to earn advertising fees by advertising and linking to Amazon.com As an Amazon Associate, Seasons of Scones earns from qualifying purchases.