Rich Toffee Brownies - Fudgy Delight - chefmelt

Ingredients

• 1/3 cup vegetable oil (74g)
• 1 teaspoon vanilla extract
• 2 large eggs plus 1 extra yolk, kept cold
• 5 tablespoons unsalted butter (71g)
• 1/2 cup light brown sugar (100g)
• 3/4 cup granulated sugar (150g)
• 1 tablespoon cornstarch
• 1/2 cup all-purpose flour (63g)
• 1/4 teaspoon fine sea salt
• 3/4 cup Dutch-process cocoa (75g)
• 1 cup toffee chunks (170g), some reserved
• 3/4 cup semisweet chocolate chips (128g), save a handful