Pour into prepared ramekin and bake for 22-23 minutes.
Don't overmix. It's easy to overmix small batch recipes and this can make your brownie tough. Mix by hand and only mix until dry ingredients are incorporated.
Don't overbake. I like my brownie slightly crunchy on the edges and nice and gooey in the middle. In my oven that is 22-23 minutes. Experiment with your oven to see the exact time that is best. If you want it more gooey, cook for less time.
You can use all white sugar or all brown sugar if you prefer. I usually use a combination.
I listed the chocolate chips as optional but I always add them! They make it more gooey.