Make the brownies: In a large heat-proof bowl, place chocolate and butter, and heat in the microwave in 20-second intervals, stirring in between each interval until melted (or set over a saucepan of simmering water, stirring occasionally).Add sugar and whisk until combined. Stir in vanilla extract. Whisking together the Eggs and Sugar for a few minutes will make the crumb light and soft, and create the slightly “cracking” effect you often find in brownies. The best way to make fudgy, moist Chocolate Muffins is to follow the same process as you would for a brownie. Add eggs, one at a time, and whisk just until combined. How to make Muffin Tin Brownies.