Make sure and read the instructions all the way through before beginning Preheat the oven to 425 degrees.
Prep your muffin tin by spraying with pan spray, or buttering with softened butter. Set muffin pan aside.
Mix your flour, salt, and baking powder in a small bowl and set aside. Mix your granulated sugar and zest in a small bowl and set aside. You will want to make sure it is well blended. If you are cutting your cranberries in half, you can leave them whole if you prefer, do that now as well.
Add butter, oil, and orange sugar to a medium-sized bowl. Mix well. Next add the eggs, Greek yogurt, orange juice, and milk. Again, mix only to combine. The flour mixture is added next. Mix to combine. Now add in the cranberries and walnuts. Leave a few cranberries out to top the muffins before baking.
Scoop the muffin mixture into the pans. You should have the perfect amount for 12. Top with a few of the remaining cranberries.
Now, mix together the ¼ cup sugar and zest. Top muffins with this. Place muffin tin in the preheated oven.
Bake for about 7 minutes, then turn the pan around. Most ovens have hot spots, generally, in the back corners, it is best to rotate halfway through.
The muffins will take between 14-18 minutes to bake. You can test with a toothpick. The trick is though, you want it to be just slightly underbaked when you remove it from the oven. The reason for this is there is a process called carry-over cooking. This means the baked cook will continue to cook even when it is removed from the heat source. The residual heat in the muffins will keep cooking after it is removed. So, make sure the toothpick has just a little wet muffin batter on it, but only a little. Another way to test it is to gently touch the very top of it. I like to bake it until about ½ inch in the center of the muffin is slightly underbaked.
Remove from oven.
Allow cooling for about 3-5 minutes in the pan. Then, carefully remove and place on a cooling rack. They are delicious warm, they are delicious cooled, and they are even delicious the day after! Make sure and wrap well if they won't be eaten the day of!