In a medium-sized pot, cover potatoes with cold water. Bring to boil, then reduce heat and simmer, just short of tender. Drain and, when cool enough to handle, dice into ¼ inch pieces.
In a medium-sized bowl, combine diced potatoes, onions, red pepper flakes, cilantro, fennel seeds, ground cumin, garlic, ginger, and salt. Mix to incorporate all ingredients.
Preheat waffle iron. Beat eggs in a large bowl until fluffy. Next, beat in flour, milk, vegetable oil, sugar, baking powder, and salt, just until smooth. Mix in the samosa filling until well-combined.
Use non-stick cooking spray or brush oil onto preheated waffle iron. Follow the manufacturer's instructions regarding how much batter to pour. I use this waffle iron and pour about ⅓ cup of the batter into each section of it. As the waffles cook, you will notice steam coming off the waffle iron. When it stops, our waffle should be crisp, golden-brown, and ready.
To keep waffles warm, set on a baking sheet in a 200°F oven.