I make little "cake"'s out of left over pellet and hay dust that you find at the bottom of the bags. I use to just throw it away but now I figured... why not make it something edible? It seems silly to waste it.
I use water and critical care to bond the ingredients together. You don't really want to overdo it with the veggies and fruits that you put into the recipe; to be honest, less is more and you may end up with a force-feeding slurry more than something to make cakes out of.
Avoid things like flour, baking soda etc. there's been some debate on putting soaked oats into the cakes and I'm sure the Guinea Lynx debate ended that it's okay to use them if you want.
Something I made - which is generally just me putting things I know are safe, tossing them together, playing with them until they stay together and then begging my pigs to eat them and show their piggy approval is:
Take 1/2 cup of hay dust
... 1/2 cup of pellet dust (from the bottom of a Burgess bag)
1/4 cup of water, plain.
critical care (No idea how much of this I used. I just sprinkled some in and purred at the anise smell)
One pulverised strawberry (a piggie approved fruit. Next I'll try them with non-piggie approved fruits like an orange, vitamin C and juice so I can reduce the water)
Mix everything together until it's dry enough that it won't stick to your fingers but not so crumby that it won't stick to itself. Think cake or pancake mix before you add the water and milk (don't put milk into your guinea pig cakes)
With pellets the method used to make the pellets stick together is steam. I abused this manufacturing theory when making my cakes.
I then separated the mix into two bowls; one I was going to bake, the other I wasn't to see which they preferred.
The batch I wanted to bake I rolled them into tight balls, put them on a baking tray and put them in an oven at 150 (DEG) for about 10-15 minutes (well, longer because I'm an idiot)
The batch I didn't want to bake I rolled into balls (into some I also added shorter strands of hay to make hay cakes) and left to dry. When I poked them and they didn't smush inwards, I put them onto lettuce leaves and gave them to the pigs.
By the time the baked bunch were done and cooled I felt a bit like Gordon Ramsey. I made a bed of parsley with more chopped lettuce and sliced celery. I then plunked the cooled cake-balls into the middle of the salad and topped it with a chopped strawberry which looked like the final scene from "101 Ways to Butcher a Strawberry" and gave both lots to the pigs.
They... um... were more interested in the veggies than the cakes, and I'm not sure whether they preferred the baked or non-baked cakes because after all my hard work they seemed to decide to wait until the night time before eating everything.
Piggy portion! )
I think I may have overbaked them to be honest though, as they looked a bit crispy when they came out of the oven! :red 