In a mixing bowl take maida, carom seeds, salt and oil (4tbsp+1tsp).
Mix is nicely with both the hands for few minutes till oil is completely absorbed in maida.
Keep it aside and let it rest for 15-20 minutes.Take kadai/wok or pan and add 2tbsp oil to it.
Add two pinches of asafetida Now add cumin and fennel seeds and let them roast for few seconds.
Add coriander seeds (crushed) and mix well. Add chilly ginger paste and saute for a minute.
Now add boiled mashed potatoes and green peas. Mix everything and cook for 4-5 minutes. Keep stirring it after every 30 seconds so that they do not burn.
After 5 minutes add coriander powder, chilly powder, black salt, salt, garam masala and dry mango powder.
Mix well and let the mixture cook for some time till everything mingles together and you can smell nice aroma.
Once stuffing is ready transfer it in a plate and let it cool down for some time.
Now take maida bowl and add some water and bring everything together and make a soft dough as shown in video.
Do not knead it too much as we do not want gluten to form. Cover the dough with plate and let it rest for 10-15 minutes.
After 15 minutes take the dough and divide it in 8 same size pieces. Roll these pieces and make small balls.
In a meanwhile heat the enough oil in deep kadai/wok for deep frying at low heat.
Now take one ball and roll it to a thin oval. If it is very hard for you to roll apply little oil on the rolling board and roll it.
Cut this rolled oval in two equal parts. Take one part and apply thin layer of water all over the edges.
Put one side of the edge on other and make a cone shape as shown in video. Now put some stuffing inside this cone and stick it together as shown in video.
Make 4- 5 samosas at a time and drop them in oil. Make sure that oil is on very low heat.
Cook samosas on low heat till they become firm and light brown in color.
Once they get light brown color increase the heat to medium and cook them till they get nice color.
Samosas are ready to serve. Serve them with green chutney and ketchup.