In a heavy saucepan over medium low heat, melt the 2 tablespoons of butter and then add the sweetened condensed milk.

Place the cocoa powder in a small bowl and whisk in enough water to make a smooth paste. Add the mixture to the melted butter and sweetened condensed milk. With a wooden spoon stir the mixture constantly , scraping down the sides until the mixture is very thick . The mixture is done when you are able to divide it down the middle with the wooden spoon and it stays parted for a couple of seconds. Remove from heat and place in a bowl. Cool the mixture and then refrigerate for at least 30 minutes.

Place the chocolate sprinkles, white sprinkles, rainbow and green sprinkles in individual deep bowls. Place the ground pistachios in a separate bowl. Place the gold foiled baking cups on a platter.

When the chocolate is firm, make small chocolate balls by using a small scoop and then by rolling in your hands to form the ball. Either spray some non stick spray on your hands or use some softened butter to form the Brigadeiros. Divide the chocolate balls evenly and roll in the sprinkles and pistachios to cover completely. Place in the gold foiled cups. When all the Brigadeiros are done, place in the fridge for 30 minutes .