It is very easy to make falafel batter, it's very straightforward.
It is not as easy to make falafel batter that doesn't disintegrate into so much deep-fried powder the moment it hits the hot oil.
1. Make certain your oil is hot. Around 200+, if you have a thermometer (I'm guessing, since a meat thermometer probably isn't that accurate for liquids... not as much as a candy thermometer would be). If not, google "falafel falls apart" and people will tell you how to tell if your oil is too cold or too hot by looking at how it bubbles. If it's too hot (I discovered this too!) the outside of your falafel nugget will burn and the inside will be undercooked, OH NOES. (Or, as I did, cook until the outside's done, peel the crust away, and refry. XD)
2. make certain your paste is cold. COLD. Not, "hey, evaporation!", REFRIGERATE. (....yeah, so guilty of that one. XD)
3. if you use canned beans, your paste will be too soft and wet, aka Not Thick Enough. It will. Yes, it will. Don't believe anyone who tells you different, it WILL because YOU are the White Man, ethnic food behaves thus for you. You will have to add flour, a slice of bread, something. Wheat flour will change the taste and texture some, it's wheat flour. But! Garfava bean flour is -gasp!- ground raw chickpeas (garbanzo) and fava beans. Coincidentally, this is EXACTLY what falafel is made of. I added very liberal amounts of this, to get it plaster-thick and gluey. (Bob's Red Mill makes garfava bean flour)
4. I hear rumors that actually soaking dried beans overnight and skinning them prevents these problems. Next time I do something the not-shortcut way, I'll let you know.
5. Grind it very, very fine. Think toothpaste, not salsa. Not even fine salsa. HUMMUS, people. Food processor or meatgrinder, whichever... blenders are not your friend. (...guilty of that one too)
And, for those of you with a "stray cat" sense of cuisine (such as MY BROTHER), burned falafel powder fished out of the cooled oil tastes like burned beans, burned onion, and burned garlic. Imagine that! This too was learned the hard way, though not by me. XD