1-First, gather and prepare all your ingredients: 2 cans of condensed milk, 2 tablespoons of unsalted butter, and 1 to 2 tablespoons of key lime zest. Measure them out accurately to ensure the flavors blend just right. This step sets the stage for smooth cooking and helps avoid any last-minute rushes.

2-Second, place the condensed milk, butter, and key lime zest in a small saucepan. Heat it over medium heat, stirring continuously to prevent burning, which usually takes about 10 to 15 minutes. Keep an eye on the mixture until it’s very thick and you can see the bottom of the pan clearly when you stir.

3-Third, test the mixture by tilting the pan; if it pulls away from the bottom all at once, it’s done. Transfer it to a heat-proof bowl and let it cool completely, which gives the flavors time to meld. Once cooled, lightly butter your hands, scoop portions, and roll them into balls for that perfect shape.

4-Fourth, roll the balls in sprinkles or sugar mixed with more key lime zest to add extra zest and texture. Finally, place each brigadeiro in mini paper cups for a cute presentation. The whole process, from prep to finish, takes about 40 minutes, making it a quick win for any occasion.