Ingredients:

400 grams mashed potatoes
125 grams wheat flour
5 grams baking powder
1 teaspoon salt
1 egg
5 green onions, chopped
120 milliliters milk
Cheddar cheese, shredded (amount not specified in image)
Cooking spray
Instructions:

Preheat your waffle iron to medium-high heat. Spray the waffle iron with cooking spray.
In a large bowl, combine the mashed potatoes, wheat flour, baking powder, salt, egg, green onions, and milk. Mix until well combined.
Fold in the shredded cheddar cheese.
Pour batter onto the preheated waffle iron, filling each section about ¾ full.
Cook the waffles for 3-5 minutes, or until golden brown and crispy.
Serve immediately with your favorite toppings, such as sour cream, chives, bacon bits, or additional shredded cheese.
Tips:

You can use leftover mashed potatoes for this recipe.
If your waffle iron is not non-stick, you may need to grease it lightly with cooking spray before adding the batter.
Be careful not to overfill the waffle iron, as the batter will expand as it cooks.
You can add other ingredients to the batter, such as cooked bacon, ham, or sausage.
Let the cooked waffles cool slightly before cutting into them, to prevent them from falling apart.