Heat up the sweetened condensed milk in a microwave-safe dish for about 30 seconds. Add the chopped semisweet chocolate to the warm condensed milk, and allow it to sit for 3-4 minutes to melt the chocolate. Once melted, mix until the ganache is smooth. Allow it to cool until it is about room temperature.
Whip the softened butter for 1 minute, until fluffy.
Add the cooled ganache to the butter and continue to whip until combined. Sift in the cocoa powder and pinch of salt and continue to whip the butter for another 1-2 minutes until it is light and fluffy.
Spread butter in an even layer onto a ceramic, glass, or marble board.
Dipping ideas: Chocolate cookies, pretzels, biscotti, wafers, fruit.
*Note: Make sure your ganache isn’t too warm. If it is too warm, it may melt the butter.