Preheat the oven to 400 degrees F or 200 degrees C for at least 10 minutes.

Line a muffin tray with cupcake or muffin liners. Or you can grease or spray with non stick cooking spray. This recipes makes 8 muffins.

Take dry ingredients (all purpose flour, whole wheat flour, baking soda, salt and sugar) in a bowl.

Whisk well till everything is well combined. Keep it aside.

In another large bowl, take melted butter.

Add milk and yogurt. Make sure milk and yogurt are at room temperature.

Beat it well till everything incorporated.

Now add orange juice and zest. Again beat it very well.

Now add dry flour mixture. Start mixing using wire whisk and half way through switch to spatula. Mix till everything is combined. Do not over mix.

Now add chocolate chips. Fold them in.

Divide the batter into prepared muffin tray. Fill them only ¾ full.

Bake into preheated oven for 20-22 minutes. Check by inserting a toothpick in the center of the muffin, if it comes out clean then muffins are ready.

Remove them from the oven and let them cool in the pan itself for 5 minutes.

Then transfer them to a cooling rack and let them cool completely.