Cook the green beans (on the stove or microwave) do not drain. Allow too cool.
Preheat the oven to 350°F
Puree the liver I use a food processor. I prefer lamb liver for dogs with allergies but I have used chicken, pork or beef liver. if you use beef or pork liver cut it up into small chunks before processing or the processor might jam up.
Once the liver is processed I add the cooked (cooled) green beans to the mix including the water. Process it till it is lump free. You may have to process it in small amounts till it's all done.
Put all pureed ingredients in a bowl add the instant mashed potatoes gradually while stirring. you should end up with a thick paste if its to runny to hold up on it's own add more potatoes.
Press it flat on greased cookie sheets about a 1/3 of an inch thick (more than a quarter inch less than a 1/2). The thicker the cookie the longer they take to bake.
I use a piece of plastic baffle from lighting to score the dough but you could use a pizza cutter this is not a biscuit recipe but soft reward treats so they can be made small or big depending how you want to serve them. Score the all the cookie sheets this usually make at least 2 sheets worth.
Place one sheet near the bottom of the oven and the other near the middle bake 20 minutes then trade sheet middle to bottom bottom to middle. Bake 20 more minutes. you should have 2 sheets of dark brown around the edges semi soft dog treats. cook longer if you want them firmer. remove from cookie sheet freeze all you will not use in 2 days place the rest in the fridge. My dogs all love these.