Preheat oven to 350º and prepare pans by buttering generously. Use an 8x8 inch pan, 2 nine spot brownie pans, or a 24 spot mini muffin tin.

In a medium glass bowl, melt the butter in the microwave. [you can melt the butter in a pan on the stove if you prefer, in which case, you can just mix the rest of the ingredients in that same pan.]

Mix in the brown sugar until well blended and smooth.

Mix in the egg and vanilla until smooth.

Measure in the remaining ingredients and mix until well combined.

Spread evenly in whatever pan you are using.

Bake for 16 to 25 minutes, depending on pan - the 8x8 pan will take the longest time, the mini muffin pan the shortest. They are done when they're nicely browned and a toothpick inserted near the center comes out clean, or with just a moist crumb or two.

Cool completely in the 8x8 pan, but only a couple minutes in the sectioned pans, before removing.