Peel and cut the potatoes into small cubes. Thinly slice the carrots. Cut the green beans into 1-inch pieces if they are whole.

Pour three cups of water into a large stock pot or Dutch Oven. Add 3 cups of cubed potatoes, 1 cup of sliced carrots, and the green beans. Place the fish on top of the vegetables.

Bring to a boil over high heat. Reduce the heat low, cover the pot loosely, and simmer for 20 minutes. The potatoes should be fork-tender and the fish flakes easily. Stir to break up the fish into smaller bites.

Allow to cool completely before serving.

Store leftovers in the fridge in an airtight container.