Grease a 6-inch plate and set aside. In a large, wide and heavy saucepan bring the milk to a boil over medium high heat. Let it boil for 2-3 minutes. Add lemon juice to the milk, it will begin to curdle. Use minimum amount of lemon juice to just start the curdling process and prevent the whey (milky water) from completely separating immediately.
Boil for 5 minutes and remove approximately 1½ cups of the whey liquid. This will help reduce the tartness from the cake.
Continue to cook and stir occasionally until the milk is a grainy consistency and the whey is evaporated. This will take an additional 15-20 minutes.
Add sugar and cardamom and keep stirring till the mixture starts coming together (approximately 5 minutes). Lower the heat to medium and cook for another 4-5 minutes until mixture changes to a slightly golden brown color.
Transfer mixture to the greased cake plate and press firmly then cover with aluminum/tin foil. As an option, sprinkle sliced pistachios on top.
Let sit for at least an hour before slicing into individual pieces.
Tips: This dessert can be prepared ahead of time and stored at room temperature for a few days.
It is generally a few inches tall and has different shades of color throughout. However, this recipe will make an even colored cake that is approximately 1 inch thick. This recipe makes approximately 12 servings.