Preheat the oven to 350℉.
Prepare your 9X5 inch loaf pan by buttering and lining it with parchment paper.
Toss the chocolate chips or the chocolate chunks in 2 tablespoon flour and set it aside.
¾ cup Mini Chocolate chips, 2 tablespoon All-purpose flour
In a bowl, sift all dry ingredients, including flour, baking soda, baking powder, and salt. Set aside.
1½ cups All-purpose flour, 2 teaspoon Baking powder, ½ teaspoon Baking soda, ½ teaspoon Salt
Use the whisk attachment or hand mixer to whisk eggs, sugar, oil, milk, and vanilla extract. Mix until well blended and smooth.
1 cup Sugar, ½ cup Oil, ½ cup Milk, 3 Eggs, 1 tablespoon Vanilla extract
Add this mixture to the dry ingredients and gently fold in. Use a rubber spatula.
Pour half of this batter into the lined pan.
Mix the cocoa powder and chocolate chips into the rest of the batter and pour over the plain batter.
2 tablespoon Cocoa powder, 1 teaspoon Cinnamon
Use a pairing knife to run the two batters into each other by making swirls. Tap the pan on the counter a couple of times. Bake the loaf for 50-55 minutes or until an insert comes out clean. Let the loaf cool down in the pan for 15 minutes, then transfer it to a cooling rack.