Sambar Styles

[Anand S]

My wife's sambar tastes different from my mother's. And mine, too. When I cooked as a bachelor, my neighbour would pop by, taste the sambar, and exclaim, "Rasam super!"

Surbhi's Day 5 of the 30-day challenge was about Sambar which inspired me to take her dataset and create a decision tree for which state a sambar recipe is from based on its ingredients.

ChatGPT started with 68 recipes and built a tree at 41% accuracy. As we added more recipes:

Recipes	Accuracy
68	41%
293	42%
361	55%
406	54%

... the accuracy wasn't improving all that much.

Here is the classifier script: sambar_fftree.py. You can run it via:

uv run https://files.s-anand.net/blog/2026-04-26-sambar-styles/sambar_fftree.py

But a ingredients are snipers: rare, precise, devastating.

• Kokum or goda masala -> Maharashtra. 32 for 32 in one run. Perfect.
• Sesame/gingelly oil -> Tamil Nadu. 28 for 32. Strong.
• Coconut oil + shallots -> Kerala. 22 for 29.
• Moong dal + no mustard seeds -> Andhra. 31 for 36. Better than garlic.
• Byadagi chillies -> Karnataka. 6 for 7. Tiny sample, but clean.

But without some of these strong signals, the sambar could be from anywhere. Better to abstain when unsure.

Here is the classifier that allows abstentions: sambar_fftree_abstain.py and the dataset I used. You can run it via:

# Download the files
wget https://files.s-anand.net/blog/2026-04-26-sambar-styles/sambar_recipe_dataset.csv 
     https://files.s-anand.net/blog/2026-04-26-sambar-styles/sambar_fftree.py 
     https://files.s-anand.net/blog/2026-04-26-sambar-styles/sambar_fftree_abstension.py
# Run the script with the data I used
uv run sambar_fftree_abstension.py --no-download

Only about a third of recipes have a clear signal.

Incidentally, Coconut alone is not a Kerala signal. It's more "west coast".

State	Uses grated coconut
Karnataka	60%
Kerala	58%
Maharashtra	32%
Tamil Nadu	24%
Andhra	14%

Garlic is not Andhra either. In one run, garlic + no coconut was a 50-50 split between Andhra and Maharashtra.

Rather than states, it's better to think of styles.

Style	Ingredients
Amti	kokum, goda masala
Tamil tiffin-sambar	sesame oil, sambar powder, tamarind
Kerala coconut-tempering	coconut oil, shallots
Andhra pappu/charu	moong dal, less mustard
Karnataka sweet-roasted	byadagi, jaggery, coconut

Maharashtra is easy to identify if it's amti style. Without kokum or goda masala, it's generic sambar.

Tamil Nadu sambar has two distinctive styles: sesame/gingelly oil; or sambar powder + tamarind.

With all of this, we could identify the state only about one-third of the time based on ~2,000 recipes. But we can identify the distinctive styles from their ingredients, when it's present.

Like my bachelor-days sambar, which was missing dal. (No one told me sambar needs dal.) And my neighbour could identify it instantly. As rasam.