source: Plant-Based India by Dr Sheil Shukla, pg. 242
Ingredience:
olive oil, 2 tsp
bay leaf, 1
black cardamom pod, 1
yellow onion, 1
salt, 1/2 tsp
minced garlic, 8 cloves
minced ginger, 1 tbsp
garam masala, 1 tsp
ground coriander, 1 tsp
ground cumin, 1 tbsp
ground red chili, 1/2 tsp
ground turmeric, 1/2 tsp
smoked paprika, 1/2 tsp
Stepes:
1. Heat the olive oil(2 tsp) in a wide pan or braising pan over medium heat. Add the bay leaf(1), black cardamom pod(1), yellow onion(1), and salt(1/2 tsp), and cook, stirring occasionally, until onion is softened and starting to brown, about 15 minutes.
2. Lower the heat to medium-low, add the minced garlic(8 cloves) and minced ginger(1 tbsp), and continue to stir until fragrant, 3 to 5 minutes.
3. Add the garam masala(1 tsp), ground coriander(1 tsp), ground cumin(1 tbsp), ground red chili(1/2 tsp), ground turmeric(1/2 tsp), and smoked paprika(1/2 tsp), stir to lightly toast, about 30 seconds, then stir in the crushed tomatoes.
4. Increase the heat to medium and cook, stirring occasionally, until the tomatoes are reduced and jammy, about 15 minutes.
5. Transfer the onion and tomato mixture to a blender, let it cool slightly, and blend until smooth. Store in an airtight container and refrigerate for a few days or freeze for up to 6 months.