In a medium saucepan, bring 2 cups of water to a boil. Add the green tea leaves and baking soda. Boil for about 10 minutes, stirring occasionally, until the water reduces to about half and turns a deep red color.
Remove the saucepan from heat and strain the tea into a large bowl, discarding the leaves. Allow the tea to cool slightly.
In the same saucepan, add the strained tea back in and pour in the whole milk. Bring the mixture to a gentle boil over medium heat, stirring continuously to prevent it from sticking to the bottom.
Once it reaches a boil, reduce the heat and simmer for about 10 minutes. The tea will start to turn a beautiful pink color.
Stir in the heavy cream, sugar, ground cardamom, and a pinch of salt. Continue to simmer for another 5 minutes, adjusting the sweetness as desired.
Remove from heat and let the chai cool for a few minutes before serving.
Pour into cups and garnish with chopped pistachios and almonds.