Line a metal 9x9-inch baking pan with parchment paper and spray with cooking or baking spray. Set aside.
Crack eggs into a glass measuring cup and beat well with a fork.
Microwave chocolate in glass measuring cup on 30 second intervals. Stir with a spoon until melted and smooth.
Melt butter in a glass measuring cup in the microwave. (about 30 seconds to 1 minute)
In a large mixing bowl add sugar, whisked eggs, vanilla extract and combine with an electric hand mixer or a stand mixer.
Combine the melted butter and melted chocolate, stir with a whisk or rubber spatula to combine until smooth.
Scrape the chocolate and butter mixture into the sugar and eggs mixture. Use a rubber spatula to scrape all of the chocolate mixture into the bowl. Beat with an electric hand mixer or use a stand mixer to combine.
Sift flour into a small bowl. Add salt. Whisk flour into the chocolate sugar mixture using a whisk or an electric hand mixer to combine everything until smooth.
Fold in crushed Heath bar pieces with a rubber spatula.
Pour the brownie batter into a prepared 9x9 inch baking pan. (Metal pan preferred lined with parchment paper and sprayed with cooking or baking spray.)
Use a rubber spatula to spread the brownie batter evenly into the baking pan.
Bake in a preheated 350-degree F oven for about 55-60 minutes, or when a toothpick when inserted comes out with only a few crumbs. Rotate the baking pan 180 degrees about half way through baking process.
Let cool for about 1 hour before removing from the baking pan. Let cool completely before slicing.
Notes
Homemade Brownies
You can also use ¾ cup chopped walnuts instead of crushed Heath bar.Or swirl in 1-2 heaping tablespoons of Nutella into the brownie batter just prior to baking. Use a butter knife to swirl it back and forth into the batter.Rotate the baking pan 180 degrees about half way through baking process. This will help them bake more evenly.Each oven is different, we recommend using an oven thermometer. Set your timer to 50-55 minutes. Check the brownies with a toothpick. It should not come out clean, but still have some chocolate crumbs on it. (but not be super coated in chocolate)Allow brownies to cool completely before cutting into squares. This will allow them to fully set and they will cut into squares easily.