Heat the vegetable oil over medium heat.
Add the garlic ginger paste and cook, stirring constantly until the sizzles subsides (about a minute).
Reduce heat to low and add the spice mix. Cook, stirring constantly, for about 30 seconds.
Stir in the diluted tomato paste and turn the heat back to medium, stirring constantly.
Add the peppers and onions and cook, stirring every minute or so, for about 15 minutes. You want the onions soft and the peppers pretty soft. Turn off the heat when you get there and tend to your chicken.
Once the chicken is done, let it rest briefly while you heat up the onion/pepper mix.
Serve the chicken over the onions.
Squirt a bit of lemon juice over top. That really brightens things up and brings everything together.
This goes great with Indian flatbread - think Indian fajitas...