Preheat the oven to 350F.
Pour 1/4 teaspoon of the oil into an 8- by 8-inch baking pan and grease it thoroughly. Line the pan with parchment paper.
In a medium bowl, mix together the eggs, tahini, coconut oil, coconut sugar, and vanilla extract with a fork.
Add the almond flour, coconut flour, baking powder, and salt to the wet ingredients in the bowl and stir the mixture with a fork until all the ingredients are well combined.
Add the chocolate chips to the bowl and stir until the chips are evenly distributed in the batter.
Scoop the batter into the prepared pan and smooth out the top with a spatula. Bake for 20-25 minutes. You'll know the blondies are ready when the edges are slightly browned and a toothpick inserted into the middle of the pan comes out clean. If you get chocolate on your toothpick, try another spot. (It's super melty and will coat the toothpick even when the blondies are done.)
When the blondies are done, remove the pan from the oven with oven mitts and place the pan on a trivet or hot pad on the kitchen counter (to protect the surface from getting damaged by the hot pan).
Let the pan cool for at least 30 minutes, and then remove the blondies from the pan, using the edges of the parchment paper to lift them out.
Cut the blondies into pieces. If they are still warm, be careful as you pull them apart or they will break into pieces. They'll still be delicious, though!