In a medium saucepan, combine the condensed milk, butter, heavy cream, and corn syrup.

Bring to a boil over medium heat stirring often.

Once it begins to bubble, add the semi-sweet chocolate and cocoa powder.

Whisk well, so there are no pockets of cocoa powder.

Reduce heat and continue to cook, whisking constantly until it is a dense fudge-like batter. This should take between 8-10 minutes. If undercooked, it will be too soft. If you overcook, it will be too chewy. Pay attention; it will be perfect, when you can tip the pan and the mixture slides to the side, in one soft piece.

Slide the mixture into a bowl – DO NOT scrape the bottom of the pan.

Leave out on the counter so it can cool to room temperature.

At this point, cover with plastic wrap and chill in the refrigerator for 4 hours.

Scoop the mixture by the teaspoonful. Roll in hands to form balls. They should be the size of a small truffle.

Place your chosen topping in a bowl. (see notes on toppings)

Roll a few of your candies at a time, making certain they are covered completely in sprinkles.

Store in airtight containers.

Brigadeiros will stay fresh in your refrigerator for up to 1 month. (Take my word for it, they will not make it that long)