Line a 8- by 8-inch brownie pan with wax or parchment paper, overlapping the sides for easy lifting later.
Pour some water into a very small bowl and put it in the freezer to chill (this is in case you don't have a thermometer, or if you want to be super accurate).
In a small saucepan, stir together the sugar and 1/2 cup water. Attach a candy thermometer to the pot (if you have one) and place over medium heat. Bring to a gentle boil.
Continue to cook the sugar mixture (it should bubble adamantly), stirring occasionally, and checking the temperature, either with the candy thermometer or with a regular digital thermometer. Be extremely careful; bubbling sugar will burn you like nobody's business.
When the sugar mixture reaches 230 degrees F, turn the heat off. If you don't have a thermometer, pull the chilled bowl of water out of the freezer and, using a spoon, drop a tiny dollop of the sugar mixture into the cold water. It should form long strings. This is called "one-string consistency" and it means that your sugar is at exactly the right temperature.
Stir in the cardamom and red food coloring if you're using it. Now, add the coconut and the cashew powder if using. Stir carefully until the whole mixture is an even pink hue. Quickly, pour into the prepared pan, smooth out so it's an even thickness and allow to cool for about an hour.
When hardened, pull out of the pan, and cut into either bite-size squares or diamonds. Enjoy with a warm cup of chai!