Slice the onions and reserve a fist to use later.
In a pan add 2 tbsp oil when it is hot add the sliced onions.
Saute in medium flame till onion changes golden brown.
Once done add coriander powder . allow to cool and blend it to fine paste.
If using Paprika/ Red Chili flakes instead of red chili powder do add to this mixture and grind well.
In the same pan add remaining oil, temper with fennel seeds.
Now simmer it for another 5 minutes or so.