Cake
Preheat oven to 350 degrees.
Prepare and bake cake according to package instructions.
Let cool and then crumble cake up. Set aside.
Coconut-Pecan Frosting
In a saucepan, mix melted butter, sweetened condensed milk, and egg yolks.
Stir continuously over medium heat until it thickens, about 10 minutes.
Remove from heat and mix in vanilla, coconut, and pecans.
Remove from stovetop and cool for at least 30 minutes, stirring now and then.
Cake Truffles
In a large mixing bowl, combine crumbled cake and frosting. Stir to combine.
Mold 1-inch balls out of the cake and frosting mixture.
Line a small baking sheet or another freezer-safe platter with parchment paper.
Place balls on the baking sheet and freeze for about 30-minutes to an hour.
When the cake balls are ready to remove from the freezer, melt chocolate in the microwave in a glass bowl, starting with one minute and then stirring.
Continue to melt chocolate in 30-second intervals, followed by stirring, until the chocolate has melted.
Place coconut and pecans in bowls to have ready to sprinkle on the chocolate-coated cake balls.
Using a fondue stick or something similar, pick up each ball and dip into the chocolate, setting back onto parchment paper. Sprinkle with a tiny amount of coconut and pecans, before the chocolate hardens.
When all cake balls have been dipped in chocolate, drizzle a small amount of melted caramel over each cake ball truffle.
Allow to chocolate to harden before serving, placing the truffles in the refrigerator for 30 minutes to speed up the process, if desired.