What Type of Cocoa Powder to Use: If you only have Dutch-processed cocoa powder on hand, you can use that instead, but omit the baking soda.
What Type of Oil to Use: I’ve also tried this recipe with vegetable oil and avocado oil (instead of canola oil), and they both work fine.
Storage: Once the brownies are completely cool, wrap them well with plastic wrap. Store them well-wrapped at room temperature for up to 5 days, in the fridge for up to 2 weeks, or in the freezer for up to 6 months.
If You Don't Have Unsweetened Chocolate On Hand: You can substitute with 3 tablespoons of unsweetened cocoa powder + 1 tablespoon of vegetable oil per 1 ounce of unsweetened chocolate.