Mix the salt, red chili powder, white cumin seeds and cilantro with the mashed potatoes
Cut the square spring roll wrappers in half to make 20 rectangular strips
Make a paste of the flour and water and set aside for later
Place 1-2 tablespoons of the potato filling at the top of each strip
Fold into a tight triangle, making sure the potato filling is nicely tucked in and there are no gaps or holes in the wrapper (SEE NOTES)
Use the flour paste to seal the open side and to glue down any loose flaps (SEE NOTES)
Preheat the oil and fry the samosas till they are a nice golden brown (SEE NOTES)
These samosas are on the spicy side. If you're not used to very spicy food i would recommend cutting the red chili powder in half.
Making the triangles is easy but making sure there are no holes or gaps is essential. If the wrappers are not tightly sealed, oil pours in through the gaps and makes the filling oily and the samosas greasy and soggy.
Practice makes perfect and you'll get better at making the samosas as you go along. But in the event that there are gaps, use the flour paste to seal them.
The oil must be well heated before you start frying as this helps make the samosas crispier.