Combine all ingredients and microwave in a 2 cup glass Pyrex dish for 2 minutes. Enjoy warm.
On its own, this brownie is not quite a THM:E, so if you're not using it as a dessert after an E meal that already contains some carbs, add a piece of fruit to bring it squarely into E territory for a breakfast or snack.
Notes
You can make your own oat flour by grinding oats in a coffee grinder or high-powered blender. I prefer to use a blend of sweeteners or all granulated sweetener in this recipe. I do not recommend using all pure stevia extract powder in most chocolate recipes. Feel free to add more granulated sweetener to this brownie (I'm a dark chocolate lover and most people say I undersweeten).
Recipe by Briana Thomas at https://www.briana-thomas.com/gooey-brownie-for-one/