For optional stir-in/topping: To add a little kick to these brownies, lightly brown 2 cups hazelnuts in 2 Tbsp. peanut oil. Let cool then remove skins by rubbing nuts between a clean dish towel. In a food processor, pulse nuts until slightly crumbled, then add 2 Tbsp. Mayan Cocoa and pulse until fully incorporated. Mix 1½ cups into brownie mix before pouring into pan and sprinkle remaining on top before baking.
Use 2 Tbsp. of the butter to grease two 8x8-inch square pans and preheat oven to 350 degrees. In a large mixing bowl, stir together butter, sugars, oil and syrup until blended. Stir in eggs one at a time until blended. Stir in cocoa, flour and extract until blended. If using Mayan hazelnuts, add them now and incorporate. Spread evenly into the two pans and bake for 40 min.
Serve warm or at room temperature topped with Homemade Mexican Cocoa Ice Cream.