Heat the oil in a pan on medium heat.
Once the oil is hot add cumin seed and crushed cilantro seeds (fry for 30 seconds).
Add the spices (turmeric, red chili powder, garam masala and salt. Stir the spices well and cook them for 2 minutes.
Add ginger & garlic paste and green chilies and cook for 1 minute.
Add the onion and cook for 2-3 minutes.
Now add the boiled potatoes from earlier and mix well. If you want to add peas to your filling you can put them in at this stage. Cook for 3 minutes.
Add lemon juice, cashews nuts, water and cook for 5 minutes on low heat.
That’s the filling made, put it aside and let it cool down completely before putting together your samosas.