In a mixing bowl, add butter, cocoa powder, sugar and mix until fully dissolved.
Add eggs, vanilla and mix until smooth.
Add flour and mix until just combined. Don't over-mix!
Pour batter in an 8 inch square pan, that's been lined with foil and sprayed with oil.
Spread batter evenly with a spatula.
Bake at 350 degrees F for 20-25 minuted or until an inserted toothpick in the center comes out with a few sticky crumbs. If it comes out clean, it's over-baked and the texture would not be as ooey goey.
Remove from oven and let the brownies cool to room temperature.
While the brownies are cooling, prepare frosting.
Once brownies are completely cool, spread frosting on top.
Optional but recommended: Cover and chill in fridge for a few hours, which makes it slightly firm and allows you to cut sharp clean slices.
Cut slices with a sharp knife. Be sure to wipe knife clean with a damp paper towel after each cut. Cut 9 large slices or 16 smaller slices.
Prior to serving, top off each slice with cherry pie filling, if you like. Enjoy!