I refuse to feed my horse anything containing excess sugars or starches. If he's getting home made treats, they're homemade by the produce guy at the grocery store and are usually long, skinny and orange.
The only treats I buy are the Manna Pro Nuggets. They are the only thing I've found that aren't entirely made out of "junk food" for horses.
I love that I'm not the only one who doesn't bake for their horses
I have given them bites of bran muffin so I'm thinking you could just bake some of them (prepackaged ready to bake of course).
I tried once to bake a horse cookie when I was thinking there had to be something better than whats out there, but its waaaay to much work.
I give mine one or two of these every day Majesty's Animal Nutrition - Home Page