Preheat the oven to 350°F.

Grease a baking pan well. Lainey used a 9-inch pan in the written recipe and a silicone pan in the video.

Add the butter, unsweetened chocolate, and white chocolate chips to a medium saucepan.

Melt over the stove for about 2 to 3 minutes.

Stir continuously so the chocolate does not burn.

Add the sugar and mix quickly.

Remove the saucepan from the heat.

Let the chocolate mixture cool for about 3 minutes.

Place the saucepan back over low heat.

Add the egg and whisk quickly so it does not clump or cook.

Add the vanilla extract and mix well.

Add the self-rising flour and mix until combined.

Add the baking powder and continue mixing.

Fold in crushed Oreos, walnuts, peanuts, or another optional mix-in.

Pour the brownie batter into the greased pan.

Spread the batter evenly.

If excess grease appears on the surface, gently blot some of it with a paper towel, as shown in the original video.

Bake at 350°F for about 20 minutes.

Remove the brownies from the oven.

Allow them to cool for about 10 minutes.

Leave the brownies plain or sprinkle powdered sugar over the top.

Slice and serve once they have cooled enough to hold their shape.