In an effort to save money after getting tired of the outrageous prices or store bought horse treats, I made up what is probably the easiest horse cookie recipe in the world. The base only takes two ingredients and every horse I've met has gone bananas for them.
My the horse cookie recipe goes like this:
Instant oats (though I'm sure about any kind will work)
Take some old (like sitting in the fridge at least 2 weeks) apples. Peel them, core them and cut them into chunks. Put them in a bowl and mash them with a potato masher (I like the potato masher because it leaves some little chunky pieces) or some other mashing tool.
Take instant oats and begin mixing them in slowly, to avoid the mixture being too dry, until the concistancy is thick and mold-able.
At this point you can add any extras like carrots or a bit of molasses.
Roll into balls about the size of a medium marble
Bake on a baking sheet lined with parchment or wax paper for a minimum of 1 hour at 350f. To check if the cookies are done tap one with a spoon, if it doesn't feel completely solid its not cooked through.
These cookies are meant to be very hard and crunchy so don't worry about burning them. Just give the pan a shake every half hour or so, so that the cookies roll around and the bit touching the pan doesn't get too dark.
(keep in mind adding something like molasses has the potential to make them softer, adding any type of sugar may also cause them to burn easier)