• 1 ⅔ cups all-purpose flour (208g)• 1 cup granulated sugar (200g)• 1 ½ teaspoons baking soda• ½ teaspoon table salt• ½ cup natural cocoa powder (50g)• ½ cup very hot or boiling water (118ml)• ½ cup canola or vegetable oil (118ml)• 1 cup sour cream (240g) (see note)• 2 large eggs lightly beaten• 1 teaspoon vanilla extract• 2 cups semisweet chocolate chips divided (340g) (I like to use a blend of mini and regular-sized chocolate chips
Pour cocoa powder into a separate heatproof bowl or large measuring cup. Carefully pour very hot or boiling water overtop and whisk until mixture is smooth.
Add wet ingredients to dry ingredients and use a spatula to gently fold together until about halfway combined. Add 1 ½ cups of chocolate chips and mix until well distributed.
Bake in center rack of 375F (190C) oven for 17-18 minutes or until a toothpick inserted in the center comes out clean or with a few moist fudgy crumbs.