Ultimate Skillet Brownie

Bahan-bahan (8 porsi)

• 3/4 cup (12 Tbsp; 170g) unsalted butter
• 2 Tablespoons vegetable oil
• 4 ounces (113g) bittersweet or semi-sweet chocolate*, coarsely chopped
• 1 and 1/2 cups (300g) granulated sugar
• 3 large eggs, at room temperature
• 2 teaspoons pure vanilla extract
• 1/2 cup (42g) unsweetened natural or Dutch-process cocoa powder*
• 1 cup (125g) all-purpose flour (spooned & leveled)
• 1/2 teaspoon salt
• 1 cup + 2 Tablespoons (about 200g) semi-sweet chocolate chips, divided
• optional for serving: ice cream, salted caramel sauce, and/or hot fudge sauce