Step 1

Preheat the oven to 350°F. Line a muffin tin with muffin wrappers.

Step 2

In a medium bowl, whisk together the flour, baking powder and salt. Set it aside.

Step 3

In the bowl of a stand mixer fitted with the paddle attachment, beat together the butter, oil and sugar on medium speed until well mixed. Add the eggs, one at a time, beating well between each addition.

Step 4

Reduce the mixer speed to low, then gradually beat in the flour mixture, sour cream and vanilla just until combined. Fold in the raspberries and chocolate chips.

Step 5

Divide the batter among the muffin tin cups, filling each full.

Step 6

Bake the muffins until a toothpick inserted comes out clean, 25 to 30 minutes.

Step 7

Remove the muffins from the oven and let them cool slightly in the muffin pan before transferring them to a rack to cool completely.