Best Homemade Raspberry Muffins

The original recipe comes from www.aburstofbeautiful.com. As usual, I've modified it to reduce the sugar significantly, add chocolate chips and substitute whole wheat flour for half of the flour. I'm loving these muffins!

Ingredients

1 Cup milk
1 Tbsp white vinegar
2 1/2 Cups flour (half white, half whole wheat)
1 tsp baking powder
1 tsp baking soda
1/2 tsp salt
1/2 Cup sugar
1/3 Cup vegetable oil (or softened butter)
1 egg
2 tsp vanilla extract
1 1/2 Cups frozen raspberries
1/3 Cup chocolate chips
6 tsp coarse sugar

Directions

1. Preheat oven to 425 degrees F. Line muffin cups with parchment muffin liners, or lightly coat with unsalted butter or cooking spray.
2. Combine milk and vinegar in a measuring cup. Stir and allow to sit for 5-10 minutes. Milk will thicken or curdle, effectively making buttermilk.
3. In a medium bowl, combine flour, baking powder, baking soda and salt.
4. Using an electric mixer, combine sugar, oil or butter, egg, vanilla and milk/vinegar in a large bowl and mix until combined.
5. Add the dry mix until just combined, do not overmix.
6. Fold in the frozen raspberries and the chocolate chips.
7. Scoop the muffin mixture into each cup, filling it to the top of the liner.
8. Top each muffin with ½ tsp coarse sugar.
9. Bake for 5 minutes at 425F and then reduce temperature to 350 and bake for 18-20 minutes until a toothpick can be inserted and removed cleanly. (I just baked at 375 for 20 minutes or so, but I'll have to try it this way.)