Combine the oats, cocoa powder, baking powder, salt, and vanilla extract in a blender or food processor. Pulse until the oats are partially broken down but still slightly textured—you want some oat pieces remaining for a better texture in the final dish. Add the egg, agave, and oat milk, then blend until you have a smooth, thick batter with no dry flour streaks. I like to use a blender here because it creates a creamier base than hand-mixing, which makes the oatmeal feel more cake-like rather than chunky.

Lightly grease a microwave-safe bowl or mug (about 12-16 oz capacity) with a small amount of oil or cooking spray to prevent sticking. Pour the batter from Step 1 into the prepared bowl and spread it evenly. Microwave on high for 45-60 seconds, starting with 45 seconds and checking for doneness—the top should look set but still slightly moist, and a toothpick inserted in the center should come out mostly clean with a few moist crumbs. The batter will rise slightly and be tender when fully cooked.

Remove the cooked oatmeal from the microwave and let it cool for 1-2 minutes—this allows it to set slightly without becoming dry. Sprinkle the extra chocolate chips on top while still warm so they soften slightly. I find that adding the chocolate chips after cooking keeps them from burning and gives you little pockets of melted chocolate throughout. Serve immediately in the bowl or turn it out onto a plate if you prefer.