We use the Inner pot or Pot-in-Pot technique for various reasons:

1. To isolate cooking inhibitors – Tamarind, jaggery, sugar are cooking inhibitors. We use an inner pot to isolate them from other ingredients.

Eg: Sambar, Chakkara pongal

2. To prevent curdling – When cooking dairy with ingredients that may cause it to curdle, we seperate them using an inner pot.

Eg: Kuruma with milk or coconut milk.

3. To promote caramelisation – While cooking caramelised curries or caramelised sauces along with starch, the ingredients for sauces are layered directly without water. The starch is mixed with required water and is added to an inner pot.

Eg: Pasta with sauce

4. To create two separate heating zones – The inner pot cooks much slower than the outer pot. When cooking ingredients with two different cooking times, we place the easy cooking ingredient in the inner pot and the hard to cook ingredient in the outer pot. This is especially useful for ingredients whose cooking times cannot be balanced by changing their surface area by cutting them big or small.

Eg: Cooking Capsicum/ green peas with potato

By nesting many pots, we can extend this principle to cook almost everything together, irrespective of their cooking time. Even mutton and prawns can be perfectly cooked together, at one shot! This principle is further extended in the Queued cooking technique.

5. To isolate non edible stuff from edible stuff.

In some recipes where we do not want ingredients to come in contact with each other, we separate them using an inner vessel.

Eg: In Arbi Masala, we use the inner pot to cook arbi, and the onion/ tomato masala is layered outside as we do not want colocasia’s inedible skin to come in contact with the masala.

6. To make MPOS possible.

With multiple inner vessels, we can create multiple dishes by just mixing and matching building blocks.

Eg: One shot thalis with vegetables in the outer layer and different building blocks in inner vessels over them.

7. To make blending easier.

In recipes where a part of the ingredients need to be blended, that part alone is separated from the rest using an inner vessel to make it easy to remove.

Eg: Paneer butter masala, Palak paneer

8.For double boiling

The outer pot holds water and the inner pot holds the ingredients which need to be cooked in a water bath.

Eg: Poached eggs, Puddings, batter cakes,

9. To hold watery spice pastes.

In case the spice paste/ the curry paste is runny and cannot be directly layered over other ingredients, it is added to an inner vessel to prevent it from seeping to the bottom and causing burning.

10. Sugar syrup

In recipes which require ingredients to be steeped in sugar syrup, the syrup is cooked along with the recipe in an inner pot. Its consistency is controlled by varying cooking time and water quantity.

Eg: Jalebi, Jangri, Badhusha, Gulab Jamun

11. For Tadka

In recipes with just an oil buffer, a small inner vessel with tadka ingredients and oil can simulate open pot frying perfectly. Multiple inner vessels can be used for different tadkas.

We can use the outer and inner vessel combination in numerous ways, depending on what we try to control :

1. No water in the outer pot, water in the inner pot.

2. No water in both pots

3. Water in both pots

4. Water in the outer pot, no water in the inner pot.

5. No water in the outer pot, oil in the inner pot.

6. Oil in both pots

7. Oil in outer pot, water in inner pot.

This technique gives us great control in cooking different things together. It has been further extended with multiple nested inner vessels into the Queued cooking technique.