Mix in the eggs and vanilla extract. Be careful not to over mix or the texture will be more cakelike.
Melt the baking chocolate in a small saucepan over medium heat. Watch closely so the chocolate just melts and doesn't get too hot.
Slowly pour the chocolate in the creamed sugar mixture. Mix till blended. Use a rubber scraper to scrape the edge and bottom of the bowl.
Add in the rest of the ingredients and mix just till blended.
Lightly grease a 9x13 dish. Pour batter into the dish and bake in a preheated oven for 30 minutes. If you're baking in heart molds, bake for 20-25 minutes with the molds on a metal or perforated baking sheet. If you're baking in a mini muffin pan, bake for 15-20 minutes. Cool and frost or top with ganache.
Frosting
Melt the butter. Whisk in the cocoa powder and then add the milk and vanilla extract while whisking.
Mix in a ¼ teaspoon of salt and 4 cups of powdered sugar till smooth. It is easiest to do this with an electric mixer, or beaters.
Immediately spread over brownies before it sets and firms up.