1/2 cup butter (or margarine)
4 ounces unsweetened chocolate (baking chocolate)
2 cups sugar
1 1/2 teaspoon vanilla
Cinnamon to taste (or other flavors)
1 cup all-purpose flour
1 cup nuts or chocolate chips
In a 2 to 3-quart pan, melt butter and chocolate over medium-low heat, stirring until well blended.
Remove from heat and stir in sugar, vanilla and cinnamon or other flavorings. This is a good step to experiment with, adding anything you want to give a go. I've tried several different types of flavorings, but I tend to go back to cinnamon, which is why I use that in the recipe.
Add eggs, one at a time, beating well after each addition.
Stir in flour, then mix in nuts (or, in my case, chocolate chips!).
Pour the batter into a greased 9-inch square baking pan (I grease and flour). Spread evenly (it'll usually spread itself if you give it a moment).
Bake in a 325F oven for 40 minutes or so (time may need to be adjusted depending on your oven). Let the brownies cool in the pan on a rack, then cut into 16ths. Store at room temperature in an airtight container, if there are any left over.
A note on "licking the bowl"... if you trust your source of eggs, it's really an awesome batter to lick. If you do not trust your source, be careful. Raw eggs can be very dangerous.
These are best served warm with a bit of ice cream. You can heat them up in the microwave easily, just a few seconds. You can also put icing on them (cream cheese is particularly good) and sprinkles are festive. They work well as a potluck dessert if cut into 32nds with icing on top.