Gather your ingredients and measure out 1 cup of cocoa powder, 1 teaspoon of vanilla extract, 1/4 cup of butter, 1 cup of sugar, and 1/2 cup of milk. Also, chop the pecans into small pieces for later use.

On the stovetop over low heat, melt the butter in a large saucepan. Once melted, add the cocoa powder and stir until combined.

Gradually add the milk to the mixture, stirring continuously to prevent any clumping. When all of the milk has been added, raise the heat to medium and bring it up to a low boil for 5 minutes while stirring occasionally.

After boiling, reduce the heat to low and stir in the sugar until it has fully dissolved. Then add the vanilla extract and allow it to simmer for 5 minutes, stirring occasionally.

Add the chopped pecans to the mixture and combine thoroughly. Grease a 9x13-inch baking pan or line it with parchment paper, then pour your fudge mixture into the pan and spread it evenly. Place the pan in the refrigerator to cool for 4 hours or overnight.

After cooling, cut your fudge into small cubes and serve!