In a medium bowl, mash the banana until almost smooth. Place it into a medium pot.
Peel the carrots. Using the fine grate hole on a box grater, grate the carrots and measure 3/4-1 lightly packed cup. Place it into the pot along with the banana. Grate the zucchini (if using) using the fine grate hole and place it into the pot.
Add the rolled oats, water or milk, chia seeds, and optional dash of salt into the pot. Stir well until combined.
Increase heat to medium and cook the oats, uncovered, stirring frequently and reducing heat if necessary, for about 10-15 minutes until the oats are softened and the mixture thickens. (If you soaked the oatmeal overnight, simply heat it and serve.)
At the end of cooking stir in the cinnamon to taste and all the hemp seeds.
Serve with desired toppings (such as sliced banana, granola, nuts, etc). Leftovers will keep in the fridge in an air-tight container for up to 2 days. To reheat, add oatmeal into a pot on the stove-top and heat over medium heat, stirring in a splash of water or milk if necessary to thin out.