Preheat oven to 350 F. Lightly grease an 8x8" metal baking pan with a few drops of oil. Line with a sheet of parchment paper.
Chop the chocolate and add to a microwave-safe bowl. Heat in 30-second intervals, stirring in between, until fully melted. Set aside.
Melt the butter in a microwave-safe bowl, then pour into a mixing bowl. Sprinkle in the powdered sugar a bit at a time, whisking in between until dissolved. Repeat until half of the sugar has been added; set the remainder aside.
Add both eggs, vanilla extract, melted chocolate, and avocado oil and whisk to combine. Pour in remaining sugar and whisk; the batter will have some small lumps, but this is okay.
Switch to a rubber spatula and fold in the flour and salt until just combined. Next, fold in the chocolate chips. Do NOT overmix.
Pour the batter into the prepared baking pan, thoroughly scraping down the inside of the bowl to get as much batter out as possible. Smooth out the mixture with the rubber spatula to make an even layer. Bake for 40 minutes, depending on your oven temperature and desired level of doneness.
Allow to fully cool in the pan, 60-90 minutes, then grab either end of the parchment paper and lift to remove the brownies. Cut into 9 squares. Serve either on their own or with a scoop of your favorite ice cream!
